Everybody speaks well of JT, and I can confirm he has good products (have bought two covers) and is a great guy to deal with. I am sure his mirrors are superb, but there are alternatives. Heart of England, for instance, has two models (both round and as far as I know convex) and the second one has a slightly larger diameter. Now, I do not expect people to have different brands and be able to compare, but can anybody comment on the HoE model two?