RW king,
I can say nothing of the spartan, but the fella that runs a gunshop around here bought a stoeger 20 gauge over/under "and we shoot that thing constantly, more than anything else because its our only 20 gauge". He "bought it years ago to have a o/u my family could use (abuse) without me getting pissed" and "I've never had a single problem with it, never, and I don't clean it near as often as I should."
I didn't quote exact, but I'm close because I paid attention...I'm in the market for a 20 o/u to give someone else. He said its a very strait forward design, easy to take down, and well balanced.
NOT MY PERSONAL EXPERIENCE, but the man CAN SHOOT CLAYS, and most folks listen when he talks so it carries weight with me. It seemed, to me, that folks are leaning to anything other than a stoeger and spartan, so I thought I'd post this to give the only thing i've heard about either.
Hope it helps a bit, and if you don't mind let me know if you purchase either.