US had a varying number of E190s (I think they started with 25, sold 10 to Republic at some point, and then bought 5 back), ending up with 20 of them at the time of the AA merger. At US, they were based in PHL, and were used on some pretty long routes, as I remember seeing routes like PHL-MBJ on them, along with midcons like PHL-DFW, PHL-SAT, PHL-AUS, and PHL-MSY. The rest were relegated to Shuttle and a few shorter PHL routes like BOS and ATL. Incidentally, the first and only time I've experienced a rapid decompression (with deployment of oxygen masks) was on an E190 from ATL-PHL. We diverted to CLT. I don't think I've ever been on a plane that descended that quickly.