It's been a while since I've done a B&M variant but I think the only major difference in the restraints is that the OTSRs aren't split up... Still have the burdenous bicycle seat of burden, and unless they can get rid of that, then it'll still be uncomfortable (though nothing will be as bad as Apocalypse and the brakes of genital death)...
I don't think Thorpe getting one would affect Drayton's attendance, since they've gone full on towards the family and have the draw of Thomas Land... The two of them both really more focus on the local people rather than nationwide, even if both have recently expanded their 'resort' status...
There are just better options that have received high levels of praise across the board from various different manufacturers over a Stand-Up... It bemused me that Towers were looking at one for Katanga Canyon at one point recently, but I guess because of the Varney's obsessive nature towards the GIMMICK of a coaster it's too be expected...