I combine smoke with SV frequently. The best strategy is to smoke twice. I'll generally do a cold smoke on the meat prior to putting it in the bag, then cook it SV, and chill it down. Final retherm on the smoker until you can't resist anymore.
I've done side by side comparisons with pork belly smoked before, after, and before and after. Before and after was the winner.
Smoke particles are small enough to permeate plastic. If you smoke before hand, your cooking liquid is going to smell like smoke. On the second day, you will smell it from across the kitchen. But the particles that remain in the bag continue to develop as they cook, or so Chris Young said once upon a time. You get a more muted smoke flavor, but it has an added complexity. I do the final retherm smoke to add back that "fresh campfire" element that gets lost to the SV water. It also helps dehydrate the exterior and develop a proper bark (which SV alone would never give you). I have a Smoking Gun, and while it's fun, it is no substitute for actual smoke in an actual hot box as far as the final smoke is concerned. You can do it on a small scale with some items -- quail and other small birds take to that treatment well, for obvious reasons.
Also, the SVE guys are goons.
