Choice of 30V, 10A laboratory power supply up to 300PLN - request for recommendations

I've been using one for a while now; https://www.elektroda.pl/rtvforum/topic3803317.html#19424863 I was tempted to set parameters from the keyboard . For higher power I have some other DIYs. I was a bit unsure how the interference would be (after all, it's a combination of a switching power supply and analogue regulation) but it's ok.

Totally doesn't fit your guidelines, it has a max of 3A, for car installations it doesn't make a lot of sense, as does the possibility of connecting it in series to get 60V.
Maybe when playing with some amplifiers or opamps it's ok, but for a car it's a worse solution than what I've given.

If you can find one somewhere I recommend the xantrex hpd30-10, it's a piece of good old electronics.
I bought them a couple of years ago at 400£ each, I have a total of four xantrexes two on trafo and two hpd and this is already a piece of equipment for years.
They have some adventures with meter readings floating (by about 0.1V e.g.) during long operation, but the voltages at the outputs stand firmly at the set values.

When I bought my current power supplies, I gave my old ones away to friends, and now I'd like some garage-quality ones myself, and will probably end up with Chinese ones too. Because it's totally not worth it to assemble one myself these days.