I've got the 48V 500W version (which is the same as the one Whoosh Bikes sell I think [even though they rate it as 48V 250W], so UK legal). Nice and powerful, can get up all of Bristol's hills with ease. My battery is 48V, 12.5AH. I've never run out of battery, probably done around 75km between charges. Reliability-wise, I've not had any problems with it at all. It feels pretty solid, but definitely a notch below bosch/shimano (but, it was only £200...). They have just released a new version though (TSDZ2B), so unsure whether this will help with some of the issues that some people have had.
It does make some noise, definitely audible, and louder than bosch/ shimano motors. Here's a little video I made a while ago where you can hear what it sounds like (ignore the big clunk, that's me changing gear).
@Dexter bought both the motor and battery direct from pswpower, shipped from Germany in about a week.
In general, this review is pretty spot on I think: https://www.darkerside.org/2021/03/tongsheng-tsdz2-review/
The one thing I would add is that the firmware is a bit weird, max power output at around 70rpm cadence, drops off nearly completely at around 95rpm. I know you can change it, but you need to buy a seperate lead and plug it in, which is a bit of a faff...