There's an 8K full bridge amp being mass produced in China that's a knockoff of Soundigital. Sundown, Alphard, Qubed, etc. etc. etc. have all sold them and I think Robot Underground was selling them un-badged for super cheap. Shop around and weigh cost difference with how likely that particular brand is to be around to honor the warranty over the next year or two and go from there. I'm using the Sundown branded ones because I live within a half hour drive of an authorized dealer/repair shop that I know will take care of me if anything happens, but Sundown isn't putting anything different inside of them as any of the other """brands""".
Sadly if you buy a legit 8K half bridge amp, the first time it breaks outside warranty and the repair could potentially cost you the same as MSRP on one of these Soundigital knockoffs so for me 650$ or whatever on the Sundown for guaranteed 2 years of 8K is a pretty good buy and if it breaks this year (and can't be repaired for cheap) I'll just throw it away and buy another one.
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If $ isn't a problem you can go with a Salt, Ruthless, any Korean half bridge. I know several guys that run the full bridge amps either Chinese or Brazilian. Slapz car audio is buying them and selling them cheap from China. Imo if you want dependable your going to look at a half bridge Korean amp, they take a lot of abuse. That's just my opinion.