You should know that the G2 may start you on the road to more SureFires.
I believe the G2 should be purchased along with an SC1 (Spares Carrier - holds six SF123A batteries and a spare lamp), P60 (Spare lamp for the G2) and at least one SF12BB (box of twelve SF123A's). Looking at my G2's, I'd also get a Lanyard for it while I'm at it.
For Black (G2-BK) or Yellow (G2-YL), the Z33 TailCap [Black] Lanyard Kit is what I'd get. SureFire have an Olive Drab Lanyard (Z28) and Z26 TailCap Lanyard Ring for their G2-OD (Olive Drab).
Thinking about it, the SC1 has a lanyard (grey paracord I believe) so if you got yourself an SC1, you could attach it to a Z26 and that may save you some money.
You don't need these things for your G2 right from the start, and no other company offers so many accessories for their products (I've outlined a fraction of what SureFire offer)
But if you do get a G2, you may end up getting these accessories anyway and it would be good to have worked them into your budget now and have them to hand should you need them.
Good Luck with your choice!
Al /ubbthreads/images/graemlins/grin.gif