Hello Captain Jack!
I'm glad you too are intrested in this little boat.
Some details; she is 58x14,5cm, draft 5cm and weight 2.3kg in my version.It's made of ABS, hull, decks, superstructure and funnels. You could certainly build her with twin screws, I thought about it too but went for the easy way and used the propshaft from the kit.The kit is for the beginner as it doesn't come to any scale and there are no drawings but when you add some details from the scrapbox it came out really nice I think. I found her to be suitable at scale 1:87, that gave me an opportunity to put some HO crewmembers on board. I think I paid some 60pounds for her and it's really a bit overpriced but now that she's finished and a real joy to me it's forgiven. I post some more pics for you, hope they can be of some help. Would be nice to see if there are any other out there with this kit and what you have done to it.
Good luck.