I purchased a HF helmet a couple of years ago. It took some time to get it adjusted as far as the times and sensitivity, but it works great. I am sure it isn't made to last, like the high dollar ones, but it was only $50. If it breaks now, and I have to go buy another one, I am still ahead.
It does take some getting used to the auto darkening helmets. I was used to flipping the helmet up to see things, and sometimes still have to because of the limited lighting on what I am welding. My welder is an old Sears Mig, and the wire is "hot" all the time. That leaves alot of opportunities to accidently strike an arc. The autodarkening helmet protects from that, if it is in place.