Most of the anecdotal stuff in company seems to be around them being a little slippery. I tend to feel that they slow down a bit like a 319 (ie. they don't like slowing down, and with a tailwind I'm more prone to drop the gear earlier), and people seem to think that they're more prone to float when landing. While that may be the case, every landing's different anyway, just look out the window and flare appropriately to reduce the rate of descent! Personally, I think they're quite nice to land.
The handling differences between a standard and sharklet 320 are certainly less pronounced than going from a light 319 into a heavy 321.