I got a new (used) Tele today and it has a string-through bridge, which is supposed to increase sustain, but it actually sustains less than my Affinity, which just has the crummy toploading bridge. The guitar is in desperate need of a setup. The frets feel rough when I bend, and the action and frets are way too high for my tastes.
@Davey - I understand a bit better now, I was just taking a ride on my high horse a bit (I do that sometimes).
About the Bigsby. Yes, it will still work with a string-through body, but it just might leave some ugly-ass holes that you might need to plug.
Personally, I don't know how much a TOM bridge will affect overall tone, but then again, I'm one of those guys that doesn't even believe that body wood makes a detectable difference to tone. A TOM, however, will affect the accuracy of intonation, in a very positive way.