1.) It has been said more than once that Newark is far worse than Philly with regards to ATC delays.

2.) The OnePass program is mediocre, but I don't really think US is any better when it comes to redemption. Hopefully CO will give you good *A redemption options.

3.) The E190 is really not an RJ but a 737-lite. So, that's a bad comparison. US (Express) operates many tiny regional aircraft (CRJs, ERJs, Dash8, Saab,
etc.). In fact, about 200 of those types combined. CO's RJ fleet is pretty much just E145 and CRJ200.

4.) The coach seat is probably a subjective discussion because many have commented on how much nicer it is. But it is coach and the seat pitch is roughly the same.

5.) No surprise about the fees. They're all doing it (except WN).

I think what people have found about CO is a much more customer-friendly airline and a premium product that is worth it to those who pay for it (by way of real cash or earned upgrades). You're right - caveat emptor.

But I don't think you'll be much happier with DL at JFK. They have quite an RJ operation there, and the ATC delays are no better than EWR.