I've got a couple. It had been quite a while since I've thrown a Rhyno before I got them, so I don't have much to compare them too. They're not super flexible (no where near as gummy as the picture makes them look). They feel pretty close to my soft Ions. Also, they're not all 175g. Of the three I ordered, two were 175g and one was 172g, so if you prefer a lighter weight i couldn't hurt to ask...and if you definitely want a 175g I would specify it.
As far as how it flies...when new it was a brick. No glide (even for a Rhyno) and it would fade hard and early. With any hint of a hyzer release it wouldn't go anywhere. Its a little more worn in now and will hold lines a lot longer than it would initially.
EDIT: The above was about the XG, not the R-Pro