Hitachi and for the most part totally rebuildable. AMK are not. Performance is the same. And yes, any knock off brand of either one is garbage. Arnott being one of few aftermarkets that I trust along with Dunlop, which is really just a Hitachi rebrand.

 

I had a Arnott on one of our LR3's and it was crap.'ll go for a Hitachi given the choice.
I also dab some DeOxit grease on every connector I undo on my LR3, trying to keep the oxidation and corrosion at bay. It's expensive but a small tube goes a long way, I've been using it for years and still have some left.

 

That is surprising. They have a lifetime warranty for US customers (only two year for other markets, not sure why), which is one reason I bought one. That and I have had experience with Arnott over the years on other project cars.

 

The warranty only applies to the original owner, and when I contacted Arnott customer service they offered to sell me a new one at MSRP. All I needed was the connector to the motor which had melted, but that was not available. I ended up eventually replacing it with a Hitachi. I was glad to have a Gap tool to change the firmware from AMK to Hitachi.