I'm glad many of you are liking the reverb in the SMS. True it's not a spring emulation and I know it doesnt' work right for everyone. It is a medium length hall algorithm.
Fortunately, there are plenty of other ways of getting reverb out there. What's nice about having the reverb in the circuit is that it blends in parallel keeping the guitar's dry signal 100% pure-tube and the effect is blended along with it exactly like how a Twin Reverb blends the spring return back into the circuit. That topology is real nice when it comes to keeping the signal path all pure and minimal like Jerry's rig had it.
I've done a few with the Belton module, and I have mixed feelings about that one. It's actually a kind of trashy, low-fi, low-resolution module with some pretty pronounced splatty reflections, but that being said, when everything gets going, it's pretty musical and fun and springy sounding. It's a bit more slappy than Jerry's spring sounds, but it does get nice and wet. The module I use is designed by David Simpao using a fairly high grade processor and custom algorithm he designed. He was a chief designer years ago at Alesis, and has been running his own company for a few years and providing effects modules for amplifier makers. What I do is slightly brighten the send into his hall algorithm to go for a similar tonal voicing of a warmish fender spring sound, but it's definitely not a spring sound, it's a hall type. Seems to work ok for some but doesn't nail it for everyone. I find that with the Jerry tone settings and with everything dialed in, it's a pretty workable and good quality reverb for Jerry sounds.
... and it's just like any other day that's ever been...