Compatibility between headset and adapter

I am thinking about buying a bluetooth headset which is v1.2 compliant.
The adapter I have is of v1.1. As indicated in some documents, v1.2 is
compliant with v1.1 but have some huge improvement. So the question is:
Will these two devices work together?
btw: the best way is to buy one and test. but I guess I will not have
chance to return the headset for some reason.

Thanks a lot.