Play as many strats as you can, and get the one that's got the best balance of feeling good in your paws, and having great resonanance/accoustic volume/note seperation. Electronics can be changed, and the fact you're here suggests you've got the right idea.

It's also worth noting that G&L and Tokai produce good strat-a-likes, in fact I'm pretty sure G&L was Leo Fender's second company, I guess he missed making guitars after selling his stuff to CBS.
As for Marshall MGs, if Jim Marshall doesn't regret putting his name on stuff like that, then he bloody well should. I'd have released them under a squire type thing. Your best bet is to, as said, get hold of a cheap Laney or Epiphone all valve combo, although the Laney is probably your best bet. Peavey are good and inexpensive too. I see LC-15's on e-bay and second hand quite often, and they're in the £150 region brand new now. Randall have a pretty good rep which is mostly established through their solid state gear, but as far as I've seen most of their gear's aimed at a more metal crowd, which is great if that's what your after, but if you want a nice valvey overdrive for rock or blues I'd look elsewhere.