I love my Newtons! They are primarily great edging shoes, yet do most things well. They fit my feet really well. They are not so uncomfortable that I can't wear them for longer climbs. The chisel toe works well in thin cracks and pockets. Five Ten Stealth C4 rubber is simply the best. These puppies stick to everything well. I climb primarily trad style up to 5.11 or so - usually on granite and schist (New England). These have become my trusted partners on all my harder climbs except smearing slabs.
They offer decent sensitivity but are certainly not world-class in that department. I feel that sensitivity has improved with break-in; or it could be that I'm just now totally used to them and feel confident in them.
The upper is made from a faux leather that FiveTen calls 'Cowdura'. This is great in that it has good feel and doesn't stretch. One problem is that it tends to retain odor a bit more than other fabrics. It isn't a huge problem, but these shoes are just a bit stinkier than other shoes I've owned. A small price to pay for such perfect performance for my climbing.
Sizing: my street shoe size is 8.5. My newtons are a size 9. I was surprised at this. Usually I have to size down from my street shoe size.
My ability surprisingly outgrew my FiveTen Huecos this summer, moving from 5.8's to 10s, and I was on the hunt for technical, yet comfortable climbing shoes. Needing more toe box space but slimmer on the heels, the Newton fit superbly and remains relatively comfortable throughout multipitch climbs during the summer; the light coloring and padded tongue help in the area. I found the Newton is a wonderful toe-jamming and edging shoe, really surprised myself how these things can hang on to the thinnest burrs found at Dome Rock and Suicide. They are, however, not as stellar on slab as I would have liked, but then again, I hate slab! Comfortable, good lookin' expensive shoe. And yes, I did notice that they smell much worse than the Huecos ever did!