I have been using them since 1995 & have no problems with any parts that I have gotten from them.Some things are a little pricey, but you get what you pay for. I like the history behind them too speek's for alot.
I haven't heard of anybody doing it , but the Idea did cross my mind a couple of times , cause the 2tc & 3tc engines are more popular around here than the A14.
From my own exp. 11:1 would be as high as I would go on pump fuel, & in some cases that would be pushing it , depending on how much timming your running & such.
I live here in the U.S. & the 1400 in my 1200 came out of a 78 Datsun b210 GX . I order all my parts from my local parts store so I know they can get 'em . Just make sure you get the right pistons cause there is a diff. in the cc's from 78 & 79.