Welcome to CPF. If you have been lurking prior to your first posts you will have noticed many threads, and posts on the 6P and G2. If you have not been visiting CPF prior to posting I encourage you to do some searching. You will probably finds hundreds of posts about the virtues or otherwise of the 6P and G2.
My simple thoughts about both are that the G2 is a great light, light and can handle the P60 lamp assembly with no problems, and the P61 LA for short bursts, so as not to melt the plastic lens (window), which extended uses can do, or at least will cause distortion of the lens (window). The G2, while ok for incandescent use will not serve you well with very high amperage LED drop in's, as the body will not absorb heat from the LED. The 6P can handle incan LA's, as well as LED drop in's without real heat issues. Again, simple thoughts from me about the G2 and 6P, because there is more to be considered.
Bill