Hello Jagger.
Unless you are set on starting with a kit? May I suggest, as an alternative ,you find in the back issues of model Engineer, or bye hs book, Full descriptions, drawings, and instructions to build using only a lathe Stewart Harts trilogoy of engines.
He starts with an open frame ‘horizontal mill’ engine, then moves on to a ‘vertical cross single’ and the last a ‘reversable winding engine’. each engine is a little more difficult than the last.
I am still on the mill engine, nearly comlete? but looking forward to starting the ‘Cross Single’
I hope this helps you decide, kit, or do it youself!
All the Best
Mac