I have two HHA models. One I've had for a lot of years. Would I say they are the best? Not on your life. To be able to objectively make such an assumption I would have had to try every one made and that ain't happening. Almost every sight maker has one now due to their popularity.
I would say HHA is one of the better ones. From experience over almost 4 decades I refuse to have a sight that has plastic parts. Plastic can crack and break and I've proved it a few times. No more cheap sights for this man. I ight have a new bow every year, but the sight moves from bow to bow, year to year.
HHA does have probably some of the best materials (almost all metal), and a guard that protects the pin like no other. Bright, almost too bright most of the time--even in dim light.
If they have one drawback it would be their weight. A touch heavy, but then they have no thin stamped out parts. It's almost entirely 1/4"machined aluminum. They can last a lifetime and come with a lifetime, no questions asked, warranty to prove it.