I've done B6 Mint, AA Business and AA First.

IMO, the rankings for seating are:
1) Jetblue Solo suites
2) AA First
3) AA Business
4) Jetblue paired Mint seats

Mint is a really excellent inflight product. It's lousy that lounge access doesn't come included but if you have Priority Pass/AMEX Platinum then you get free access to the respective lounges anyway.

From a ground product standpoint even AA Business whips Mint.