I looked into buying one of those tanks when PA had some "old stock" ones on sale a few months back, and I read a lot of reviews that said the valve behaved just as you described - and just like in posts 3 and 7 it does not get much better with use. Plus, as you say, the gauge is too basic for accurate filling. In the end I decided not to buy it due to the valve, so if you really don't like it and PA will take it back that is something to consider - a good valve is not that cheap, unless you are willing to go Chinese (and who knows how long those last) . . . I do have one of Brancato's slow flow valves on a Guppy, and that one is great to fill from - very easy to control the opening point, and even at "full blast" it is manageable, filling most guns (no more than 100 psi per second gain into 250 cc reservoirs at full speed).
Do know that if you regulate it, the regulator itself will "waste" a lot of air if you have to charge it up and vent it with each use - there is more space in those things than in a microbore hose on its own, and that space has to be charged with air that can't be used. If you have a valve after it, like an Edgun Easy fill, you at least won't have to vent it every fill, but each venting of the regulator is lost air (not a big deal if you fill yourself, but matters if filled at a dive shop). But that is getting as expensive as a new valve . . .