Well, I had a few days with the LF clone this weekend. Didn't blow up.... So that's something lol.
The fan is a bit quieter than the sanway 20q.
Power wise? Nothing audible, nothing noticeable vs the sanway 20q.
Reliability? I guess only time will tell.
I could barely tell a difference between my unbridged 14k and my unbridged 20k, the difference is like maybe 1db, except that the 20k can power 4 subs and thus has about twice the power density and value for the money!
If you have a large array of subs one or more 20k's will be the better-value, if you need unlimited-power into a single 4-ohm load then a bridged 14k is about as good as it gets.
The Sanway 20k and XBS 20k probably both burst about the same (somewhere around 14-16kW I'd guess), and so unless you really really push them hard with sustained sinewaves or such, then you probably aren't gonna be able to drain the capacitors enough to notice the difference, and even then the difference isn't gonna be more than 0-3db.
On measured paper the dual power supplies probably help some, but in the real-world, beyond heating water-elements, you'll be hard pressed to tell a big difference...
A massive increase in Watts doesn't always (rarely) translates into a massive increase in acoustical-db's, the rest is turned into coil-heat and heat-sink heat. The only time that isn't true is when the number of coils and channels increases with the amplifier count, then you get a predictable increase.
Short of living in a small reinforced concrete coffin there is no practical way to hit 180-194db, or even 150-170db for that matter. As soon as you have windows, doors and ducts the SPL escapes.
It is sort of like approaching the speed of light, every bit more takes exponentially more resources.
Going from 2kW rms to 4.4kW is barely 3db, and few amps go any louder for a given channel (and if they do... it's probably <1s burst-only type stuff.)
You'd basically have to have something like: 4 SHS-24's or 32's and a TermLab to even think of being able to detect any acoustical difference; smaller cones would probably bottom/melt before the amplifier hits the limits and a UMIK-1 doesn't go loud-enough neither.
