I say, good call.
They are nice in damp and cool weather. Not really a total game changer in freezing weather though, as the cold just kind of seeps in everywhere else.
I like Oxford, which offers several types of grip options, around $80.
If you opt for Oxford, get the newest version (v.8 controller), which offers 5 heat settings, an auto off feature that actually works (unlike their previous ones), and a more simple wiring harness (does away with an underseat box and some wiring and literally becomes a two wire hookup).
Other options are Hot Grips, Symtex, Twisted Throttle, Suzuki OEM, probably others. Of these I have also used the Symtex ones, which are inexpensive and go under your existing grips. They are decent, though the included switch is prone to failure. I hear the OEM ones are not terribly warm but I have no experience with them.
Oxford sport grips with V.8 controller: