Firstly, 240sx don’t come with 200hp stock its more like 145-150 whp, and yes it will cause you to lose a fair amount of hp. The reason behind people buying auto 240’s is simple, if the body is in GREAT shape and its cheap buy it, as you can always change the the tranny. Isn’t cancer harder to get rid than a flu? same ways, rust spreads quickly, whiles a tranny can be changed any time down the line.