Best call of duty 4 custom classes?

May be...

my curent setup is a m4 carbine with red dot. bandolier,stoping power, and deep penetration

M16 w/ red dot sight, frag grenades, stopping power and martyrdom. Much of it depends on which map you're playing. For example in Wet works I always use a LMG. Some people think Martyrdom is cheap, but if you want to level up quickly you will get a couple extra kills per map.

I had great fun with the big m60 light machine gun with red dot, nicknamed the chugga chugg with double tap and deep penetration, with extra fraggs or claymores for S&D, like a superfast cannon in your hands.

But now I usually swap between m21 and the m4 sniper.