No regrets. Chalk it up as the cost of enjoying a hobby, which brings excitement and requires building your knowledge. If you have cans you don’t use as much anymore, sell them second hand and use the proceeds towards new gear. As we are all on different stages of the audio hobby progression, beginners can get into the hobby by buying well cared for gear at a fraction of the new price. I think cans are just one part of the bigger hobby picture. DACs, amps and music library also provide a source of technical learning and appreciation. The question is, what would you have spent your money on otherwise? If the answer is alcohol, drugs or partying, I’d say spending your money on audio has been a wise choice (haha).