Simple. $$$$$... we are by far the highest-profile operator of the POS, especially with Airways pairing their fleet. Embraer is likely giving them away to us at this point, and throwing in a few virgins to boot. Really was hoping to see a seat in Fifi sooner rather than later, sigh.
I've been on the E190 for the past 2 years and whilst I've had some MX issues it really has been no different from my previous 2 1/2 on the A320.