The 35s looks like a fairly nice calculator. I bought a 33s a while ago hoping it would replace the 32SII I use on a day to day basis (2 line stack vs the 1 line of the 32SII), unfortunately they decided to use weird slanted keys for no reason, which makes it really hard to use. I ended up sticking with the 32SII. I'd love to get my hands on a 42S, but they seem to sell for $3-400 on ebay.
Insofar as modern scientific calculators go, the 35s is pretty darn good. It's supposed to be the spiritual successor of the 32s line. In terms of functionality, it's pretty reasonable, and for the price you can do a lot worse. But w/r/t build quality, user experience, etc., it's still not the same.
And yeah, that 33s was a travesty. You said, "they decided to use weird slanted keys for no reason", but unfortunately they did have a reason: they wanted it to appeal to the younger crowd by having it resemble a mobile phone. How many hairy-eared engineers are going to flock to that?