May be OK for first time players. 

I've only been playing for a couple of years, so not much arm speed yet.  

On my first throws with it, it was way more understable than I expected.  It really took me by surprise.  It was basically unusable.  The one I had (and sold) was 159g.

The plastic had a nice feel to it, and the stamp was beautiful. 

I was told that the opto air diamond is the disc that all the seniors use.  Well, I'm 73 so I bought a 145-gram bright red diamond.  I was surprised when it immediately flipped over on my first throw and sailed out of bounds to the right.  For my next throw I put just a little hyzer on it and it quickly turned to the left and faded off to the other side.  I made a sincere effort to throw it perfectly flat on my last throw and it gently turned right just exactly like it was supposed to do; however, my smile turned upside down when it suddenly faded sharply tto he left and hit a ditch hard at about 250 feet.  I'm not sure about this disc, but I think these super-light weight discs are more unpredictable than I would have thought.

I picked one of these up for my slow arm at Colorado altitude. Because of the thin air here, it's not as understable as the numbers suggest but it's still pretty darn understable. The Opto Air plastic is so light that I can get massive distance out of this if I throw it right. Throw it hard and flat and it will turn and burn for me. Throw it with a touch of hyzer and it will flip up and glide into the sunset with a slight fade at the end. Great for downwind shots as well, would not recommend for headwinds.

Perfect driver for beginners.  I have average arm speed at best, but I can get this disc to flip on a hyzer backhand and it seems to glide forever.  Currently the longest distance disc in my bag.  The only issue I have with it is that it will go wide right if released flat or with any anhyzer (RHBH), but that's probably more user error than the actual disc itself.  Definitely a must get for newer players.

I traded for this disc last summer. I was looking for a good fairway driver that I could launch with a backhand, and I definitely found it here. I would absolutely recommend this disc.

I like it because it's my hyzer disc. But if I throw it well it stays straight the entire time.

Profile: Small width, thin disc. Great for all ages

Flight:  Understable flight, perfect for those learning to backhand.  Once you get 250' power you won't throw this one, it will most likely cut roll unless you hyzer flip it

Comparison: Less glidey more understable Leopard

Final thoughts: Best kids/new player disc out? Quite possibly.  This is one of the easiest discs to learn to backhand with.  The rim is small enough that kids do well with it.  As you start to gain more power this is a wonderful disc to learn to hyzerflip with too.  If you are just getting into disc golf do yourself a favor and pick up one of these.

The Diamond is my favorite disc. Lightweight and easy to throw. Perfect for my small hands. 

I have 3 Diamonds. Air, Opto and Prime. Air is my favorite and what I drive with the most.

Found a lightweight one in some blackberry bushes. I can't throw it without it flipping sideways and rolling. I don't have a very strong arm, but this thing is way too understable even for me.

Like every version of te Diamond it is easy to throw and a great disc to learn to drive with. The opto version gives a more consistent flight path and does not turn over as easy as the Recycled or Test Material versions. Highly recommend for all new players who struggle with distance and controlling their drives.