I've been 'experimenting' with convexing a few blades lately. I've done mine with 220/320/400 grit wet/dry sandpaper on top of my strop block (about 1/16" of leather thickness). I am liking the edges I'm getting, and the bonus is, these edges are tailor-made for the strop afterwards. Very easy, smooth, effective stropping. Knives I've done so far:
Buck 112 (older 2-dot w/440C blade)
Buck 307 stockman (all three blades)
Western L48A hunting/camp knife
Old Timer (Ulster USA) barlow
small stainless 'Zippo' (Bradford PA) lockback
The small 'Zippo' knife really surprised me. Inexpensive little knife, a gift from a Navy buddy of mine (many years ago), with his ship's logo on it. I'm assuming this knife has something akin to Case's 'Tru-Sharp' stainless steel for the blade, similar to 420HC. Took the best edge of the bunch so far.
I'm also really impressed with how the 440C Buck 112 turned out. Used it to cut up some boxes, and the convex edge went through it like a laser. Very simple to touch up afterwards on the strop.