I have on occasion, and when working on custom array types I've added support for being offset with optionally compile-time known offsets. As StrideArrays.jl matures and I write more libraries making use of it, I may use 0-based indices more often. The idea of dynamic offsets when they aren't needed bothers me, even though I've benchmarked that as being pretty meaningless. The bigger problem is just that OffetArrays are a wrapper, and there's a Julia bug where TBAA information on wrappers often gets lost, so that the compiler reloads the pointer you're loading from on every iteration of a loop. Aside from that being slow itself, it also causes the autovectorizer to fail. This causes a severe regression when it occurs. Performance should be fine in other cases. LoopVectorization or `@simd ivdep` should also avoid the problem.

For the most part, my preference on 1 vs 0 is weak, and for coffee other people are likely to look at i do want to make it easy to understand / not full of surprises.