What ditch the 1655?
A question of RAM, is it for me(or in this case you)? Do you currently either use DVD+/-RWs or s/w like InCD. If you do then RAM will have benefits. If you use s/w then you can remove it . RAM discs will last a hell of a lot longer, more reliable than DVD+/-RWs. If you don’t currently do any of this you could be getting a RAM capable drive just for the sake of it.
However could the 1655 be the last decent BenQ drive with the current situation with Lite-On. RAM drives are about to speed up (from 5x to 12x, maybe more), so perhaps putting off a RAM capable drive would be advisable now. If you want scanning with RAM then Lite-On do one. SHM-165H6S.