I've had no problems on KL--in fact, I would argue that the KL oepration is very efficient compared to the other European ST partners...

...rhetorical question: How long does it take one to transfer from an intercontinental to a intra-Europe flight in CDG/FCO? Compared to a transfer at AMS?

I travel back and forth from BOS to MAN every other week: BOS-AMS-MAN on DL numbered tickets (006). Because the BOS-AMS-MAN starts on DL, I can theoretically check 3 bags for free as an elite; on my way back (MAN-AMS-BOS) my first leg is on KL and I can only check one bag and pay 50 EUR for each additional. This sucks but is the way it is: DL and KL could care.

As a side note (and I'm sure I'll be called a dink by most FT'ers), I always charge the additional bags to my DL Amex card and then dispute the charges -- just to be miserable. KL can take my money but I won't let them have it easily!