Personally i have the rx480 version of sapphire nitro+ and i haven't regretted getting it. But i hear very good things about the msi gaming card, and if it had been priced similair to the sapphire version, i might have gotten that one. - I just don't think it' worth the extra money.
So i would say buy the msi version if you think the price hike is fine, otherwise buy sapphire (it has it's advantages also).