It's quite a long time since I bought my resonator, so I don't have a very clear memory of which types I tried out on the day! My Ozark is definitely a single cone / biscuit bridge type; I remember also trying a couple of Stagg resonators which I believe were spider bridge. I seem to recall the Staggs sounding a bit mellower, but fundamentally still like a resonator - definitely some difference, but probably not enough that you'd mistake it for a "normal" acoustic guitar.
If you are able to get to a shop to try a couple, it might be worthwhile to. But if not, I don't think the type would make too much difference - a biscuit, spider or tricone are probably all equally capable of making their presence felt against the accordion!