I've found these to be the most reliable underrated putters out there!  I can putt flat and it will hold that angle and than hyzer in.  Best putter in the game! 

This is one of the floatiest putters I've ever encountered. I had issues often hitting the basket on longer putts, but with this putter it's highly predictable and glides often for me, straight into the basket. I started using these recently but will stay in my bag for a long time. I would recommend this putter to anyone without a ton a power in their putt.

I own Mercies in four different plastics: Zero Medium, Reprocessed, Opto, and Opto Moonshine.  I loved each of them for different reasons.

I putted with Zero Medium for about a year and loved it.  As a putting putter, the base plastic Mercies are glidey and very straight.  They are quite deep for a putter, which feels good to me but is entirely up to personal preference.  As a throwing putter, Zero Medium started out as an incredibly straight point-and-shoot disc.  They beat in over time into a nice late-flip understable putter that will gradually drift right (RHBH) and maybe pan out into a fade.  For short approaches it will fly straight and grip the ground/chains.

I used by Reprocessed Mercy interchangeably with the Zero Medium and found the same results.  They were the most "premium" plastic I could get a Mercy in for a while and felt better for driving than the Zero Medium.  However, the Reprocessed discs beat in to be just as understable as the base plastic (albeit slower).  This is the only Mercy I do not bag since it flies the same as the Zero Medium but with poorer grip.

Opto Mercies are the hardest to find, but they are worth the wait.  Thrown full power they glide on a frozen rope and land softly.  I've sent them out well past 350 feet with virtually no left-to-right movement.  At very low speeds there is some slight fade at the end of the flight, but generally an Opto Mercy will take whatever angle you give it and hold on until it runs out of steam or hits something.  They're my favorite one-disc-round option with pinpoint accuracy as long as you hit your line.  My only complaint is that only a few runs were ever made.  It will take you a long time to find one and will not be friendly to your wallet.  But this is a disc I will never hit the course without.

I bought a Moonshine Mercy (Infinite VIP run) so I would have a backup for my Opto in case (God forbid) something happened to it.  I ended up with a new breed of my favorite putter that I can only describe as shockingly overstable.  I know Moonshine plastic has a reputation for adding some stability over Opto, but the Mercy I have in this plastic flies more like a P3 than its namesake.  It will pan out of an anhyzer release at low speeds and performs equally well at high speeds (it can even be power gripped).

In short, the Mercy is a great putter and will give you unique flights according to which plastic you're throwing.  As such, they offer something for everyone and they have my highest recommendation.

I am a spin putter from Kansas and this disc is perfect for holding a straight line in all weather conditions.

This disc. I love it. I had only ever used the Aviar before this disc, and this one reminded me of that, but with even more glide (which, as a beginner, really helped me develop my putt game) and was even great to use for longer distances out, as it flies very straight and seems to just float. The plastic feels great in my hand, and the rim holds well for my style of push/spin hybrid. Recommend for anyone to use this, as it's my primary putter now.

I used the Mercy as my main putter for 2.5 years. I tried many putters before that, including the classics, but the Mercy always felt best in my hand. They have just the right amount of stability too, to provide confidence in spin putting and putting from distance. After they break in a bit, they develop some great glide, making them excellent for jump putting. I recently switched to P2s to go with something more stable, firm, and a little deeper, but I will always keep at least one medium Mercy in the bag for straight to turn over upshots and short drives. Growing so comfortable with the feel of the disc through putting with it for so long, I feel better throwing it as well. The oldest one I have is my go-to for turnover throws and 50+ foot jump putts. 

For a spin/push putt hybrid, this disc holds a straight line for a while, even outside 60ft. It has great grip, but isn't quite as durable as I thought it would be. For throwing, it flips up quite a bit for me and has great glide; It holds whatever angle it's on after the initial flip.

I've gone through 20+ putters and finally ended up on the Mercy. I wanted a putter that I can putt with and throw off of the teepad, and man does this deliver. This is the straightest throwing putter I've ever thrown, and it'll glide very well. I had my first paid ace with this disc on the best looking line I've thrown off of the tee, and I've had more ace runs than ever with this disc. I've also canned quite a few field aces from within 200ft, and have learned to jump putt pretty well with it. The pure to me is a very thin putter which was what I used to putt with, and the dagger felt too thick when putting with it. The Mercy is the right size between the two for me, and I've massively improved my putting game with it. I don't feel like it fades too fast like a lot of discs with a fade rating of 2 can do, and it holds up in the wind pretty well. If it's a pretty gusty day I'll pull out a P2 instead for approaches, but most of the time the Mercy is where it's at.

Update: This is still my main putter. I throw this on straight approaches, and putt with it. I have 7 of them now, and I have no intentions of going away from it.

#lawdhavemercy

There's a good reason that this hashtag exists. This putter saved my game at a time when I was trying hard to find my putting stroke. The Mercy, is just amazing. IT has all the glide, and HSS you need to make for a beautiful disc, for both putting and upshots or drives.

The Mercy will help you shaves strokes off your game, but in and outside the circle, and when you need to get it close and have it settle for that tap in. It's a putter that just wants to get into the air and show you just HOW much it really can glide. With my spin/push hybrid style of putting, I found myself draining more and more putts from 30, 40, 50 feet and beyond than ever before. The confidence comes racing back and the putts just start falling in... 

Simply put, I HIGHLY suggest you go out and get yourself a couple of Mercy, and try them out TODAY...

I've seen lots of reviews on this disc and everyone seems to love it. I am sure it is a fantastic reliable putter but sometimes the flight of the disc can't outweight the feel in the hand. When I'm choosing a disc to be my main putter, my primary attribute of the disc I look for is how it grips in my hand. To me the Mercy just didn't sit in my hand and made me feel uncomfortable about my grip and when it comes to putting confidence is more than half the battle. Three different putters can behave the same way in the air but have slightly different profiles and for me this just wasn't the right one. Thats not saying it is a bad putter but you gotta make sure it feels right in your hand.