Yes on both counts.

The Quaife feels like a very old gearbox in comparison to the R&D, and I'd never buy another one (Quaife). I think the gearbox is probably the best part about my car (although the modified wheel arches are nice - but thats another thread! lol)

The only issue I've ever had is with regards to getting spare parts, as mentioned below. But I hasten to add, this has only been to replace parts as a precautionary measure (e.g. first gear). It still worked perfectly, but had signs of wear, which is not surprising due to the number of standing starts I do. So it was easier to replace it whilst its stripped apart being checked over as opposed to waiting until it breaks.

Jeff