I have 2 Acecare tanks - a 6.8 liter, and a 3 liter which I use for tethering.

I haven't even had them for a year yet, but I see absolutely nothing wrong with them. From what I have read they have a good reputation and are used more extensively in Europe as compared to the U.S.

Of course much of the higher use in Europe may be due to the fact that Europeans accept the CE certification on these high pressure vessels, whereas in the U.S. the 'DOT' certification would be required. It sounds like you already know that you can't get a CE certified tank re-filled at a U.S. shop, since you plan on getting/using your own compressor.

The DIN 300 fill adapters normally sold with Acecare tanks (or elsewhere on eBay) are just O.K. I have had little pieces break on these, like one of the wings off a bleed valve knob, But in the end they still end up working.

But my preference is definitely to spend a little more money on the fill adapter, get a better quality hose and other components. Something like the StikBoy adapter works great.

StikBoy
 
Acecare tanks are as good as any, but my biggest issue with them is that they have M18*1.5 thread pitch. This means you have to use the lesser quality M18*1.5 valves from China. If they made one with a 7/8-14 thread pitch that would allow them to be matched up with a better valve, I'd be more enthusiastic about them. Most of the valves I've seen offered for them are not very good as compared to the U.S. made valves.
 
Excellent point Humdinger and I totally agree.

The Acecare valves are not nearly as nice as the one on my buddy’s Omega tank. It works but it doesn’t compare to the smoothness and ease of “just” cracking the valve open like the Omega.
I paid $200 for my Acecare and then another $150 for the Stickboy. Definitely brings that great deal down a bit.

I also looked for a new valve but ran into a dead end with that metric thread.




 
When I bought mine I didn't need or want the valve and fill accessories. I got a better deal ($20 shipped) on a basic DIN valve from another site. Metric valves may be less common in the US but are pretty much standard everywhere else. I also have a US-made Luxfer SCBA tank made for the export market and it has metric threads and a DIN valve. I am equally happy with both tanks and valves.