When I heard that 53 was releasing their own stylus to pair up with their amazing app "Paper", I was all over it. I absolutely LOVE paper, and I have tried a lot of styli in the last year or so, but most of them were horrid or just meh. The one I ended up keeping was the Wacom Bamboo Stylus, but it too left me wishing for more. I also tried more sophisticated bluetooth styli, but I couldn't get friendly with the various offerings from other manufacturers, so when 53 announced that their stylus was a bluetooth stylus too, I was doubtful.
However, 53 didn't try to reinvent the wheel. Their app is already excellent, responds well to speed (slow drawing means thin line, fast drawing means thick line) and blending, and therefore their Pencil stylus doesn't need pressure sensitivity or all that stuff that doesn't work well anyway, so only has a couple of features, but those are well thought out and in my opinion, important.
1. Palm rejection. Works fairly well. It can probably be improved, but so far, I'm happy.
2. Eraser. The coolest thing about this stylus is the eraser. You don't have to push some weird button to change the stylus to eraser - you just turn it around and use the end of it. It's so natural, and it works.
3. Pairing is so easy. You don't have to go into the settings of the iPad to connect with bluetooth. You just use the stylus tip to hold down the button within the app and you're connected. Or unpaired in a flash, if you want. Just like that.
4. Now that the app knows you will be working with a stylus, you can set it up so that the only thing you will be doing with your fingers is blending. Just like you would with chalk on regular paper. Works flawlessly.
Pencil is flat, but lays very nicely in my hand. The wood feels amazing. It's very light, but has just the right heft to it. I imagine with time, the walnut wood will become even more smooth and beautiful. The walnut version also has a magnet which will stick to the smart cover of the iPad. I'm sure they will fine-tune the software in the next few months, but I already love mine. I even started drawing again.