Nah, it was with a Quasimodo. The Marauder had taken a lucky LRM TAC to an engine crit a few turns back, so the Quasi warmed up the TSM and ran up a hill right next to it. Land a close-range VSPL shot to a side torso, widen that hole with a double-strength kick that takes off said torso and the XL engine within...and bing bang boom, he's more or less solo-killed the biggest monster on the battlefield with almost no damage in return. Needless to say, that one turn convinced me of the Quasimodo's worth. O0
As for Ultra-10s, I always double-tap them, unless the numbers are REALLY bad. Combine 'em with the Direct-blow rules in TO, and I find landing both shots on target is actually pretty common. Makes Siroccos FUN. >:D