There's no wrong JAA license. Any license issued by a JAA member is valid and has the same right and privileges in all JAA land. There are many that do their PPL in UK, CPL in Germany, IR/ME in Spain and fly in Italy. It's just an example, don't take it ad literam.
There might be some minor differences between the CAAs in JAA countries, but they all stick to JARs so any license issued by one is recognized by the other.