PMR Rail is one of the better choices in your price range, I would get a GOG product over it. PRM comes with an aftermarket reg as stock and some people argue incredible ergonomics with its grip setup. The GOG woodsball version SP1 or whatever its called is going to be water resistant, more efficient on air due to dwell settings out of the box. But they're both spool valves so it's pretty much the same marker. If you get a 4500 tank the air efficiency is not going to matter so much though. You generally aren't carrying 800 paintballs on your person. And Halos are great, but it's overkill. You are better off spending some of that money on knee pads. It's not speedball and you don't need to lay down a solid stream of paint, chances are you will be playing against a lot of rental players and it's pretty unfair in a lot of ways to the rental players. Same with speed feed it's overkill and junk gets in your hopper in the woods. If it rains its not usable either, whereas the GOG products are. The Enmey (spelling?) is old school pneumatic no batteries and its much better for foul weather. Kingman fasta at 50 bucks feeds 15bps, in manual no one is shooting 15BPS realistically. So a halo at 20+ is even more overkill. You gotta remember admission and paint gets pricey so I wouldn't focus on a high end hopper. Barrels are cheap to find on ebay btw. You only really need two I keep the stock barrels on my Razors which are pretty darn good and the autococker came with a 3 bore Kaner kit which is sweet. Usually the .690 is the do it all though with regular field paint.
I end up playing with my autococker a lot just because it can be overkill playing with a hopped up electro against rental players. Don't forget a pod belt or harness. Tom Kaye of Airgun design pretty much has disproved almost every theory of paintball physics that is out there. Longer barrels, one gun being more accurate than another etc..etc... Ultimately if you have a gun whose reg is consistent + - 10 fps let's just say, your sweet spot for solid hits is really about 60 feet, maybe 80 feet max. Someone with a Tiberius or longbow barrel can maybe hit me at 120 feet, yes, but that paintball is not going to break as its lost enough energy to prevent it from breaking when it hits a person. People used to always hype up apex barrels on their A5's about how great it is, meanwhile they are lugging around this stupid long and awkward 15 pound gun with a ridiculous barrel length on it and their gear etc...etc... trying to compete against kids with a 6 pound and compact tourney setup gun. You tell me after two hours which equipment makes more sense running around the woods. Note Tom Kaye proved any barrel longer than 12" is pretty much useless.
PS if you are looking for a solid marker look into the differences between spool valves and poppet valves like the Planet Eclipse Ego and Etha. The PMR and GOG products as spool valves are basically the same gun. You'd be able to find a PE combo with an ETEK, Etha or older but equally gorgeous 06-08 EGO for about 300 ish or less if you get lucky. These are really bullet proof markers. A $1,000 new in 07 eclipse will still shoot solid even though it sells for $250 in 2013 vs buying something that is $250 new off the back.
My Ions which I bought as a discontinued model came completely hopped up with the works, magnetic trigger, alum frame, QEV, etc for $199. But it had like $500 in parts in it. So its something to think about. I see that you keep looking at new markers but also consider older super high end models. If you are looking at the PMR new why not check out the DM series used, the DM is the pro version. They can be a bargain. Out of all those choices I would personally get a GOG and be done with it or a used ETEK if it were me searching for something new. I also wouldn't hesitate to go old school and non electro. Like a prostock Autococker for $150. I have a lot of fun using my cheapie Trilogy Pro against electro guys just for the fun of it.