I got mine here in Sweden yesterday, I love it! The only thing I had problems with was the small white costar pins on my Filco that were lose so I had to glue them to my spacebar etc. Seems like the the holes on these keycaps are a bit too big.
Teobaldi supposed that's THE most permanent way. But, I rather stuff paper napkin bits into the cap before I put on the Costar stab fins to secure them without the gooey mess.