Any experience with MR-X6A Endmill grinder?

So I was wondering if anyone has experience with one of those endmill grinders Link:




They are made in China and sold by lots of different resellers. They can for example be found as:
-MR-X6A
-Knuth FSM14S
-Bernardo EMG 30 Pro
-....

Those machines can grind the faces of endmills including backrelief aswell as the flutes of 3,4 and 6 flute endmills. Over the years I collected probably 20kg of high quality carbide endmills from german brands. For my small "hobby shop" I can't justify the price of sending them out for regrinding, expecially since I only need a dozen or so endmills in a couple months. But now I have the option of buying one of those grinding machines used for ~400-500€ and I was wondering, if anyone can recommend those or if they are junk? If they are any good, this would be a no brainer for me and I'd buy that right away.

Here are some of my carbide endmills that could need a resharpening...

Don't know about the grinder, but at the very least if you plan on regrinding tools don't throw them all together to bang and chip up the flutes. At least wrap some tape around them.

It's even more important if you have an endmill with 1.5" of flute and you only used up the last .600 of the flute cutting so all you would have to do is cut off the used end of the endmill and regrind the face to have a factory cut diameter.

I would imagine that you get what you pay for would apply here.
If it were me, I'd save up some more money and try to find a better quality one.

You can get used industrial one, like little surface grinder with fixtures in decent or half decent condition for half of this fine chineseum. I'd opt for that