whatever class you may be.. which other class do you like working with on a team? we all know each class has different attributes and some are best suited in certain situations.
Soldiers - We have all been their when we have dry mags on both weapons... then you thank the solider who resupplies you just in time ready for another wave of enemies, or you have just been ambushed and from outta no where a molotov comes screaming past your face into the mob giving you those vital few seconds more to react.
Engineers - You just ran into a group of mediums, open fire and half way through the clip you back around the corner thinking your [censored] is going to get pushed in when they steamroll around the corner, then all you can hear is the continuous fire from a tripod mounted death machine followed by a volley of hot lead seemingly finding its way into the enemies face ultimately saving your hide from getting curb-stomped. Not to mention the handy damage amplifier to give your bullets a little extra 'Kick'
Operatives - The silent assassins... There the reason why you're turret is now firing at you, sneaky and perfect for getting behind enemy lines making his/her team jobs easier by spotting mines and generally been a nuisance as you watch some poor unsuspecting noob who got excited about incapping you casually lowers there scrotum onto your face... but what he didn't know was your skull is outfitted with the latest in explosive technology. i call it the Scrotex Bomb... BEEEP BEEEPPP BOOOOM
Medics - 13secs left on the clock to successfully complete a class specific objective and from out of nowhere you get incapped, your the only one with the right class to finish the job off as other people are too far away... you start too feel rage as for the past 15minutes you have been fighting hard to reach this point.. as you see the WIN slip away, a lightweight darts around the corner throwing you the vital piece of equipment which could possible turn the tide. After injecting yourself you quickly make a B-line for the objective taking it at the very last moment.
Those are just some examples, personally i find working with someone who's an engineer is quite a deadly duo, you can keep both supplied with ammo...he can keep your weapon buffed and covered by using the turrets also setting traps at chokepoints.
Whats your choice and why?