What is the most overrated/underrated unit in CM

[DerBlitzer]

Under-rated: smoke. I use it all the time, particuarly on attacks, and especially from tanks, but find that many of my PBEM opponents don't bother with it at all. Many prefer, I guess, not to waste a precious 60 seconds on something that doesn't harm the enemy. Yet smoke is an incredibly useful method for creating mobile barriers to any kind of enemy fire and preventing those dreaded flank attacks. (Not always realistic, though---you can't area fire through smoke at a unit you know is on the other side, so it can act like a solid barrier, but it probably comes close to simulating the actual effects.)