I've never tried the Pure Grips. I would probably try them just based on the fact that so many guys on this site think they are the best, but the one thing that I'm leery of is that the Tour Velvets are my least favorite grip and the Pure Grips look a little bit like them.
I still have a bunch of Tour Velvets in the closet that I'm pretty sure will never be used because I just don't like them at all. I thought I could get rid of them by putting them on my wife's clubs (she's not as picky as I am) but she started using something else also.
I did stick one on an old persimmon head driver I re-gripped a few days ago because I'm not likely to hit that club more than a few times, and just messing around with it.