I don’t have one of that type, so I haven’t contacted them. I was thinking about getting a unit like that, but then found out why they weren’t in stock anywhere.
I think the lack of drain was intentional so that the water wiuld splash up on the condenser coil. An AC unit generates a lot more water than a refrigerator though, so I think any design with a condensate basin below the condenser coil will have mold problems. The other issue is they didn’t make the unit very serviceable, so opening it up to clean out mold sounds like a huge hassle. Draining the water away will mean the units won’t be as efficient as originally designed, but mold can be a major health hazard.
I don’t have information specific to midea, so there is some speculation, but I do have a ge unit which does outright say that the water condensate is slung across the condenser coil to boost efficiency. And yes, my ge unit got really nasty and I ended up drilling a hole in the base of the condensate pan to drain all the water.
https://products.geappliances.com/appliance/gea-support-search-content?contentId=16758
Heat pump efficiency is limited by the temperature delta across the compressor. The larger the temperature delta, the less efficient a heat pump is. Evaporating water off the condenser coil drops the refrigerant temperature compared to air only and gives a small boost to efficiency. I don’t think it’s a big difference, but it’s enough to be worthwhile doing if you can “get it for free.” Unfortunately, a constantly cool and wet pool is a great breeding ground for mold and pathogens that you don’t want airborne.
As for cleaning ease, I based that off of comments (on reddit I think), recommending people push midea to pay for a technician to perform the fix because taking it apart for a thorough cleaning is a hassle. So I have no firsthand experience there and I’ll defer to your judgement.