I have used up almost every freewheel except a White which I have ridden but it's beyond my budget....

Dicta's Suck....don't use one ever when they blow up its always painful. you get what you pay for
ACS Claws are cheap and mostly reliable but annoying in a start and no two will ever feel the same (I have four 18T ones that I have switched between on my BMX cruiser)
Suntour, if you can find one, is nice,
Shimano's are annoying....I wanted to like mine but it just never performed predictably.
AC Racing I've had 3, 1 failed and was replaced gratis by the LBS that sold it to me. I sold one for twice what I paid for it Sold one on a bike I foolishly sold and I still have a 15T in my part bin. They are a little disconcerting because they are quiet and you can't feel the engagement like some of the other freewheels....requires a Shimano BB tool
Origin 8 made a really nice freewheel that can still be found on the web....probably second only to White in quality about $50 if I remember right
White Rolls Royce of freewheels, they are sweet if you run an 18t spend the extra $$ on a Trials
ACS Crossfire I've only tried one but to be honest I didn't notice a lot of difference compared to the Claws freewheel though they do look better and are supposedly made from cnc'd parts instead of stamped parts...plus there is the whole new tool required thing
Excess Components these guys are new they seem to be a bunch of disgruntled BMX racers who are displeased with Cassette hubs. I just put one on my Race Cruiser I haven't hit the track yet but I done a couple of mornings on my local trails...amazing engagement, good sound and cheap $25plus they have a cool looking tool but you don't need it stock 4 tooth freewheel tool works fine