My 2-cent-worth:
from my own limited xperience, each hv its own +s & -s:
1) local AB:
+ warranty
+ full service records (embedded in the key, even if people temper with the car..)
+ climatized to M'sia tropical conditions
- usually have minor problems, like, broken auto/memory seats (at least on 4/5 local 525i I checked out so far...)
- not assembled in Germany..
2.) Japan Recond
+ usually low mileage (although this could be tempered)
+ usually very well-taken-care-of internally
- radio & navigation doesn't work!
- not climatized to our climate
3.) UK Recond
+ Readily compatible systems (radio, nav, etc)
+ CBU from Germany
- usually with high mileage and some hidden rusts
- not climatized to our climates
- usually drivers in UK are a lot rougher than in M'sia & Japan..
Since my own xperience on the "un-climatized" disadvantages on recond cars have been okay so far, I would say, if you could a find a GOOD UK recond, then go for it! Nothing could beat a German build quality!!