I agree - registry transfers are best avoided.
For starters, you don't know what mods have been done to the plane off the books.
A few years ago I wrote up an
article on transferring G to N which will indicate some of the pitfalls. In essence, you need to be 100.00000% sure that all will go smoothly before you deregister the aircraft, otherwise you will end up in a legal limbo from which there are only 3 ways out:
1) Pay whatever it costs to sort it out (could exceed the aircraft value)
2) Dismantle the aircraft and cart it on a trailer to a different company, which is willing to sort it out
3) Scrap the aircraft
I am in contact with many many pilots so I get to hear lots of stories, and some of them are pretty horrific. Getting grounded for months and spending 5 digits is common in registry transfers within Europe. The FAA is no pushover (the DARs can be extremely picky) but Europe is a whole different level above that. One chap wanted to put a plane onto the Greek registry and the process they insisted on was similar to a 747.