There's no reason you should have to adjust the needle valve daily. Once you have it set, the bubble rate should stay put until cylinder pressure begins to decrease. Also, I posted this on a different member's thread about Milwaukee quality, and I think I'll just keep it saved as a stock response whenever there's a question:
The Aquatek, Milwaukee, and Azoo, and their clones, will all be functional. But they're single stage, and low quality, and are far more likely to bust than any of the used industrial regulators many of us use and repurpose for our needs. In addition, there will be an increase working pressure as the cylinder nears the end of its fill, potentially causing problems unless you keep a careful eye on the pressure.
Furthermore, the needle valves on those units are identical, and extremely imprecise. They're functional, but barely so.
As for the solenoids, I've read little to suggest they're any more likely to fail than many of the other solenoids we've tried over the years (reasonably likely), but mine did, in any case (I had a 3M, nearly identical to a Milwaukee).
Generally, responses will vary from "love it" to "will never entertain the possibility of using one again in this lifetime", with nothing in the middle. Basically, you get what you pay for. In this case, the all-in-one rigs are cheaply purchased because they're cheaply manufactured.
I'd recommend getting somebody here to build one. Or reading the build-your-own-regulator sticky in the equipment section and piece it together yourself. Or getting one prebuilt from greenleafaquariums.com ...anybody familiar with any other companies building rigs?
To be fair, you'll definitely spend more, possibly a lot more, if you go any of these routes (building your own can cost even less, but there's a nasty learning curve, and shipping costs for multiple sources can get ugly). However, the quality upgrade is ridiculous.
However, because of the low cost, there's definitely a place for the bottom-rung regulators. If you want a cheap intro rig, that you'll certainly upgrade from at some point, and you're willing to chance a malfunction and put up with their drawbacks (though, to be honest, you won't notice some of them until you upgrade), then a Milwaukee isn't a bad deal.