What are some recommended Weapon Customizations for Bad Company 2?

I already use UMP-45 with 4X Optics and Magnum Rounds for Engineer, and I'm doing pretty good with it, I can spot and kill people at long-ranges with it as well, it's also a fast kill, and I normally fire in 1 to 2 shot burst at medium to long range and 2-3 shot burst in close range combat. For Recon, I use the GOL Magnum Sniper which is very accurate and has less drop than the M24 and the M95, easy Head-Shots but I'm not very good at hitting moving targets, sad to say :( I use C4 instead of Mortar Strikes. *Takes too long to get there* For Medic I have MG63 or whatever it's called, the one with the built-in Red-Dot Custom Sight, it works fine, I use it all the time, any other recommendations?