You dont need to put your car on a roller for an MOT, any reputible MOT center will have a portible Gforce center that can be used inside the car on the road.
Also, my recomendation is to take it to the Import shop in Gadebridge. They have a garage that does MOTs, there often leaniant with Modified cars as the dealership its attatched too sell imported modified Supras and Scoobys etc all day long so they are well and truily used to them.