There’s basically two big disadvatages of the open-frame Meanwell PSUs: one is that you have a direct connection from inside the case to 220V (or 110V), not a problem if you know what you’re doing, but maybe something that is sometimes a bit underestimated (as in, you might expose yourself to electrocution if you don’t do things properly). The other downside is noise and ripple. This is a much more complicated subject and a lot of people will tell you very different things about it.
My personal opinion and experience is that in most cases you can get away with a Meanwell if you stay clear from badly designed modules (but how do you know a module is badly designed? There’s some very popular brands, which have some rather badly designed modules) and wire things up properly. There’s also some types of circuits which can raise the noise floor: compressors, VCAs that amplify beyond unity gain, distortion, wavefolders, mic preamps etc. In some cases you might hear the noise more, in others less (eg. a distortion is might be less probablematic).
There’s also different types of noise. I have 3 different cases here: one that runs from a Meanwell RT-65B, one with 3 TipTop Zeus boards (not uZeus). The Meanwell makes a pretty characteristic high-pitched whine, the TipTop sounds more like analogue white noise.
I did check the peak values of the noise I have in the system (not a scientific test, just something to see how much noise I had) and the Meanwell was around -70dB, while the TipTop was around -80dB. 2 different systems with different modules, so I take these figures with a pinch of salt. Fact is, if I record 10 tracks from the Meanwell I get to hear the noise really well, it’s more audible also because of the spectrum. The one from the TipTop gets masked much more easily by the actual music I’m making.
Would I buy another Meanwell, probably not? Does it work, yes, but you need to be aware of the limitations. It’s certainly not the best solution, it’s also not the worst, likely in the lower spectrum quality-wise, but it’s cheap and easily available.