Stripe and Braintree are very developer friendly, but you pay a bit more in fees. We switched to Merchant Warehouse, a firm who does cost-plus billing as opposed to flat or tiered pricing. We paid significantly less than we did with FirstData/LinkPoint. Dev integration was almost as easy as Stripe, and they have great support for payment profiles (an absolute must if you're doing recurring billing).
The biggest drawback on switching to MW is that they have a harder time articulating how much savings you'll see, especially if you don't already have transaction flow. If you do have active sales, you can give them a block of transaction data and they can show you side-by-side if their pricing model will benefit you.