If you do a search there are a handful of topics which have gone over it lots and lots of times, the forum really could do with a sticky.
CIJ (as they are now) are considered to be extremely good value for money as the QC is very very high. If you get an "alright" one it'll be better than you're standard MIM hands down (unless you get a REALLY good one), and if you get a good CIJ it'll come up to par easily against an MIA.
HOWEVER, they are a few hundred quid cheaper for a reason as they don't get all the features of the MIA Standard unless you get the higher up models.
If you want a good example of a Fender for around £500-600, I'd go for a Jap over something like the Highway 1 because you're going to need to spend about £800+ to start beating them imo.
As a side note, it's worth saying that as they new MIA Standard Range has hit the shops, prices have dropped for older MIA models to the same as Jap models currently, so it might be worth going to shops and hunting down an '06/'07 MIA.