I used to work there, was shop manager from 1988-90. It was actually called Yanks because it was originally owned by an American (Ed I think his name was). He was married to a Scottish woman, Anne. Anne got the business from their divorce. I think Ed? went back the States after the divorce.
The main business was the wholesale side, really the shop was just an added bonus for them. After the divorce, or maybe before/during?, Anne had got together with the general manager Dave.
They renamed the shop Power Cuts after doing a poll of customers. I started working there after the 1988 sale. I sorta managed to change their narrow idea of what sold as I was into much more contemporary stuff.
Everything was so cheap because of the US deletions (cut-outs). They used to go over to the US twice a year and buy container loads of vinyl for next to nothing. Albums sold for 49p were bought for 1p etc. Because these were deletions then it was quite common to find rare stuff. Cos the profit margins were so high on the US stuff, it allowed the UK releases to be sold at cost price basically, undercutting everyone else.
Also the UK label reps would sell them lots of promo stuff for cash.
Their downfall was their inability to move with the times and the volatility of the relationship between Anne and Dave. I had to really push them to move into CD's, which they were very reluctant to do.
After I left I know they did another pole of customers regarding whether to stay with vinyl. The overwhelming response was to stick with vinyl but increasingly people were buying CD's. They made the mistake of listening to what people said rather than paying attention to what people were actually spending their money on.
I think they eventually ceased trading mid-90's sometime and Anne went back to Scotland.