I got a 14 day trial last year, I thought it was pretty good so I asked for the game for Christmas. I enjoyed it, but not as much as Halo. I didn't get that far in it though since I insisted on completing every quest I came across along the way.
I voted "i dont wana pay $15" because I just payed for it the once and I thought that was enough. Don't want to have to keep paying over and over for a game that you can never complete, it's expensive enough just to pay for the 1 month.
I wouldn't mind getting back into that style of gaming though, it is a lot of fun (City of Heroes was great when I played it at a friends house). I especially wouldn't mind playing if I could get with a few BFM's and play.