Harbeth is no flash in the pan, flavor-of-the-month type of speaker. While other companies have come and gone, Harbeth has been going strong for decades. Not saying other speakers are not as good or better, but it takes real quality to not just reach the top of the totem pole but stay there decade after decade. I have heard the 40.2 and 40.3 on multiple occasions and have always loved the balanced sound. While they might not command your attention during a short demo at a store or audio show, they prove their mettle over the long run in extended listening sessions. There is just something magical about the big Harbeths ... as long as you drive them with proper amplification and give them enough space to breath.
You really can't compare a smaller Harbeth with the likes of Klipsch Cornwall. You need to go to at least the SHL5+ model if not 40.x for a proper comparison in terms of the size and scale. Many audiophiles I know and respect claim that Harbeth 40.x is the final destination they arrive at after going through many speakers over many years. If I had the money, I would go for the 40.3 in a heartbeat ... as long as I can feed them with good SS amplification.