Nice looking build of the Vosper. This kit is from the same series as the "E" Boat I recently built, & considering the vintage of the kit I was like you pleasently surprised. ( See my post on the E-Boat further down on this forum.) After seeing your build I think I'll have to look for this on to go with the RAF launch that's waiting in my stash short lost. I see you have"t included any crew figures, I hope it does come with crew like the "E" boat and RAF launch. One thing you might try is to scan in the decals that way you can always make spares in case te others become useless. The first thing I do with any new kit is scan in the decals, just in case.
Remember we do this for fun John the Pom
Memory says the Vosper (3rd series) has at least the captain (look, it's a vessel and an independant command therefore he's the captain), helmsman and Oerlikon gunner from the box art, and I think another 2 figures.
Build the "Whaleback" early so it only has the 2 turret guns and you can rob its spare deck crew (gunners) for the Vosper.