The afternoon after I posted this, I happened to plug my Jem into a DSL100, an amp I was a little bit familiar with because I'd often used it to check guitars I'd set up at the store I work at. Apart from a few nice Strats, I'd never had an opportunity to plug in anything but Epiphone
Les Pauls and Squire Strats that had come in for broken wires or restrings, so I'd never really heard the amp in full flight.
To cut a long story short... SOLD!!!