Been reading with interest.. I do have 97 540i and 2003 X5. Immediate need to diagnose issue with remote keys on X5. Looks like yellow head will do.

1. Does anybody know what is the difference between v43 and v55? I mean, how old is v43? Is it like bug fixes and minor improvements?

2. If I get 2004 530i or 2006 330, will I be able to at least diagnose them with yellow head?