[Gustav]

Yeah i'd agree that mount looks a little thin although the basic xls aren't heavy.I think squee's suggesting to triangulate the plate itself with a brace which is a good idea,(a buggy chassis brace or some turnbuckes),or you could make a thicker mount from some 1/4" aluminium angle or you could make a holder for the rear of the motor.BK make these(see pic) which makes it alot easier.
I also recommend the mod1 strobe slipper.