I have used the costco/elavon (US Bank) one for several years. If you time it right you can get reduced fees or a rebate.

The equipment or software is expensive so check that out with all of them. I cannot complain but I don't run a lot of transactions a month, generally less than 10.

Oh check out McMillian Merchant solutions of McMillian Firearms fame: http://www.mmsllc.com/