I've owned a few pairs of 5.10 shoes, and have yet to be disappointed. The rubber is sticky, the construction is solid, the shape of the last is pretty comfortable as well.
I wear between an 8.5 and 9 in street shoes normally and went with the 8.5 Stonelands shoe. The fit is snug, but comfortable enough for a several efforts on a route/boulder problem. Hook and loop closure makes these super easy top pop on and off between climbs.
The shape of the last sort of surprised me out of the box. First thing I noticed was how square the toe box was. The front of the toe is almost flat, like the old Rock Wrench shoes(bonus points for you if you know what I'm talking about). My toes don't quite go as flat as the toe box is shaped, but I still get really solid edging performance on slab and slightly overhanging rock. Decent sensitivity overall too- good blend between sole durability and performance. I would have rather gotten the lace-up's for better fit, but those have a synthetic upper so they'll stink like crazy. Going to be very thankful for leather shoes while I'm living out of a van...
These shoes are great for moderate climbing, whether it's on edges or cracks, these shoes will feel at home!
Sizing: 8.5/9 street shoe, 38.5 for La Sportiva shoes(mythos, cobra, speedsters) and 8.5 for FiveTen(Dragon, Quantum, Hornet)