I had a very bad experience with Terex (ASV), I'll never go back there again.
A friend has a cat 277, it has ASV track system that sux pretty bad. But the rest of the machine seems ok.
For mulching I went to a Fecon FTX 90, it does good in my opinion. I just got a Bobcat T-320 to use as a loader & to back up the Fecon if necessary. Haven't had the Bobcat long enough to brag about it, but so far so good.

Andy