Yeah, there was I believe, 43 different variants, and this was only superceded by the Ju-88. The Mk.XVIII was a rare version, only 18, including the prototype were built from FB.VI fuselages. Most served with RAF 248 Sqn. Prior to fitting the Molins, they'd actually done a feasibility study [successfully], using the much heavier 3.7 inch [94mm] gun, but the Molins proved effective indeed, it's 7.11 lb shell were tipped with hardened steel and had no trouble entering a U-boat's hull and creating havoc. - They were called the 'TSE-TSE' because they had a bigger bite than normal Mosquitos, worked from Predannack in Cornwall from Oct'43, over the Bay of Biscay, then from Banff in Scotland after helping-out during D-Day landings, carrying-out many successful attacks on German shipping installations in Norway; a truly grunty aircraft...[rare, like all thoroughbreds...]