I really like the 7mm's. I have a 280 and 7mm-08. I have only limited experiance with the 7x57 and have never shot a Swede.

I would buy the Swede before the 7mm Mauser. There are a lot better 7mm rounds out there but I have never heard a bad word about the 6.5x55. The numbers would give the 7x57 a slight edge but I don't think either would let you down.