Not to pile on to WN, but for a number of years I was at the Companion Pass level on WN and now am back on UA, and offer a couple of additional factors. For very short flights (like MSY/HOU), I found WN to be pretty good. I also liked the refundable tix. Once you get on longer flights (I fly IAH/BOS and IAH/SFO or HOU/OAK frequently), IMHO I find the UA product (including crew) superior. Also, lately on these routes, I find UA to very competitively priced and on IAH/BOS that UA regularly beats WN on price (E- or not). Also, WN is down to one IAH/BOS nonstop most days (some days none). YMMV. Go figure.