The MIJ Strats have often been fitted with Texas and so called vintage strat pickups and the bodies are either Basswood or Alder depending on the model/spec and a wide variation in tone can result due to this alone. I would certainly try upgrading the pickups to a set of vintage pickups and thats a matter for personal choice in the end. I have the CS 57/62's and the CS54s and both give the rights tones but I now prefer the 57/62's on my American vintage 57 strat. If I was going to get a MIM I'd be inclined towards the Classic Players as the 50's version has a 57/62 pickup fitted and the 60's version the CS69's and have the right tonewoods as well. Have heard these in use on sound files and the come across well. In fact the 50's Classic player was my other choice if I did not get the 57 Vintage. The MIM 50's Classic strats have vintage spec pickups fitted but are not same as the CS PU's and whilst a nice tone it's not the right tone in my view and lot's of our people end up retro fitting PU's on them. The Classic Player in my view is a better option.
Look at the speacs given on this site for MIJ and you will understand there can be a fair bit of variation in woods and PU's
http://www.guitaremporium.co.uk/index.p ... uitars&a=0
HTH