When Michi's 2G sat at L&R for a year, both of his front calipers had siezed slider and lock pins. Two of those were next to impossible to extract.
I suspect that any 2G (and maybe 1G?) that has sat for a while will experience some siezing of the slider and lock pins. I really don't like the stock 1G or 2G brake setup. They work fine when well lubed and new, but are a PITA when they get older.
When 2G brakes are working well with good pads the cars can and do stop VERY well. If you car isn't stopping that well please inspect your calipers or have a competent brake shop check over the slider and lock pins. I suspect that perhaps half of the 2Gs I have seen have somewhat siezed pins and have what I consider dangerous brakes. If you can not threshold brake your car from 100 km/h to zero, your brakes aren't working properly.
With my stock brakes on my 2G I could out-brake almost every car on track with high speed courses. I would gain almost all of my advantage with execcisve late braking and great braking G forces. However, I gaurantee doing this will cause you some caliper issues, as while these brakes clamp just dandy, they can't deal with the thermal loads from repeated high speed braking.
So everyone, please check your brakes! BTW, I highly recommend Porterfield R4-S for street and autox duty, and R4-E for all-out track duty. I consider Metal Master pads marginal, and stock mostly useless.