What should I do?

Recently, at a brick and mortar audio dealer, I listened to a high-end moving coil cartridge.  It sounded really good, and I was impressed.  The retail for this cartridge was more then I wanted to spend ($4500), but to make a long story short, the dealer offered me a rare deal, ($2500+tax) brand new, so I bought it.  Got it home, and carefully installed it last night.  I listened to it for about 2.5 hours.  It is really good, but I don't think (at this point), that it's that much better then my old cartridge (at least, not yet).
Ok, so this morning I played around with the loading.  Better, but still I'm not happy.  Now, with only about 5 hours on this new Cartridge, I realize that it's not broken in yet.  I'm looking for input as to your thoughts on how I should proceed.
1.  Are cartridges purchased from high-end dealers returnable (I don't want to create any bad feelings with this dealer, since he gave me such a good price)?
2.  I was told 50 hours of break-in time for this Cartridge.  Should I wait the break-in period to make any decisions?
Any thoughts on how you think I should proceed are appreciated!