The Latitude 64 Pure is a very straight putter with a good amount of high speed stability and a minimal amount of fade. I actually think that Latitude 64 is underselling this disc by re-labeling it as a disc with -1 turn, because this thing doesn't even think about turning over when thrown as hard as I possibly can. You might get it to turn and burn if you throw it in a sloppy way, but when thrown flat without any off-axis torque, the disc will stay flat. Put this disc on a line and it will hold it, and if it seems understable to you then that's just because you're used to other discs fighting out of a turn. This disc doesn't begin to turn if you throw it flat, but it doesn't stop turning if you throw it on an anhyzer. So throw it where you want it to go, and it will go there. Don't blame the disc if your throw is sloppy.
Anyway, my first impression was that the Pure seems to be a disc that is shaped like a Spike yet somehow manages to fly like an Aviar (albeit with slightly more speed and slightly less glide). I will say that I have nothing against Innova's flagship putter, and I'm sure that it's a great putter for other people, but for me I can't use the Aviar because it has an awkward outer rim. The Pure is the perfect disc for people like me who can't quite get a comfortable grip on an Aviar but still want to be able to throw perfect straight upshots that glide up to the basket, land, and stop on a dime. That straight-as-arrow shot for hitting gaps or even throwing off the tee is where this disc shines. I personally wouldn't use it as a putter, because it is a bit of a shallow putter in the hand and has no bead.
Another disc you might compare the Pure to is Latitude 64's other fast, low profile putter, the Spike. At first glance, you could be forgiven for thinking the Spike was just a Pure with grip pads. You can definitely make a Spike do many of the same things that the Pure does and vice versa, but the Spike is fundamentally an understable putter that has both more turn and more fade than the Pure. You can get a Spike to fly steeper hyzer/anhyzer lines, and you can hyzer flip a Spike to get straight lines. The Pure really only wants to go straight, and even when put on a hyzer or anhyzer angle it doesn't seem to end up as far off center as other discs with more fade. That can be a good thing or a bad thing.
As for this putter's use as an actual putter, well, I don't think it's the best thing you could be using. I can imagine that some spin putters would enjoy the low profile of this disc, but personally I find it a little harder to putt with this disc because it doesn't trap quite as much air underneath it. With my putting grip, I also prefer to have a bead to hold onto with my index finger, and the featureless outer rim on the Pure doesn't give much of anything to hold onto. For my game, I think that the Pure's going to be thrown primarily for upshots and even short tee shots. The rim shape makes it easy to get clean backhand and forehand throws even if you're not the greatest putter thrower, and the straight flight path makes it easier to land this disc exactly where you want it. Definitely pick one up if you need a straight, stable disc for maximum accuracy at intermediate distances.