It's not a case of B&M building 'a tester ride' at Alton, it's more of a case that B&M following Nemesis, have always had a very close relationship with the Towers and when it comes to their roller coasters, Alton always like to stand out (and always have done) and so they see what's on the drawing boards at B&M.With Oblivion, it's pretty documented, that Air was going to come first, but with the obvious design differences, Oblivion leap frogged it and I believe, following signing for the prototype dive machine, the park got the rights to the ride type for a few years, thus none were built else where for a while.Oblivion is fantastic in every way. The queueline videos build you up, each one a tad more frantic, until on the ride...a holding brake...and one final 'don't look down..' (until we lost that). Oblivion is sheer drama all over, theatre and works well for it. The ride is massive and noisy and still packs more of a punch than most other roller coasters I've ever ridden around the world. (I'd swap Oblivion for Saw, ANYDAY).In regard for SW6, on paper it looks well, nothing really, but I have no worry what so ever, that Alton will pull something original out of the bag and will continue to lead the way with their roller coasters.One final thing, Oblivion was originally planned to have an inversion coming from the underground tunnel, but Tussauds didn't want to pay the extra and in my opinion, who needs it? Oblivion is fantastic.