I run my TH350 through a 4 ohm, Thunderchild 115 and it delivers all the volume I need (just) for 250 - 300 people at indoor fundraising events, 100 people in a martini bar and small outdoor events with about 150 people. In the four years I have owned it, it has been rock solid with no issues at all.
I purchased it as a backup. If it was my primary amp I would need the 500 for the added features set: effects return/aux in and headphone jack.
I purchased it as a backup. If it was my primary amp I would need the 500 for the added features set: effects return/aux in and headphone jack.