Excellent news! I just built their Song class, I like their kits. Finally, some innovation in 1/350 injection... If I am not mistaken, this is the first 1/350 injection kit of a ballistic missile sub since the Italeri Ohio.
Ah, I forgot the Russians. There is a Delta IV from Alanger and a number of Typhoons from various companies.
And you are right - there are not many models of British subs out there at all. I wonder why?
If you should choose to order from them you should be aware that their site is very slow, at least it was for me. At times it may appear that nothing is happening but just be patient and it gets there in the end.