A GCIV in good shape OR a Diamond Professional.
The Diamond ProAm in 9' isn't bad either. Nice table. Plays great. I'm a little wary of the frame design and slate configuration...but the one's I've shot on were totally level and played well.
I have a GCIII that is in perfect condition. Bought it used, and it was 100% immaculate with no scratches, dents, wear - nothing. As if it came out of a showroom (previous owner never used it). It might be worth getting an older model IF the condition is near perfect. I'd buy this table all over again if it were up against a beat-up GCIV. If condition is equal, I'd go with the better playing features of the GCIV or Diamond Pro. Time marches on, and there's no stopping it, so older model tables, unless owned by someone who doesn't ever use it, or someone who is very anal and keeps it perfect - will not be in great shape. Most used GC's are kind of scuzzy. I got lucky.
The advantage of the newer tables - Diamond Pro and GCIV - is that they are engineered more for players. The pockets do not have that nasty plastic sticking up that you can't rest your cue on without getting that rubbery/plastic streak on it afterwards (I hate that). They sit flush on the GCIV, and even if you do scrape the shaft against it as you stroke a shot, it won't leave gunk on your cue. The Diamond's pockets are not flush, but they are a nice leather that slides well. It won't leave crud on your shaft either. Some people will say that is never a problem at their local pool hall, because they've learned to just make a closed bridge over it, or use a V-bridge while over a pocket. This elevates the cue more than if you weren't over a pocket. This is done to avoid that dredded plastic pocket. So in a way, a home table with nice pockets like a Diamond or GCIV might spoil you.....
Both of these tables have nice WIDE rails so you can really get your hands on them for nice bridging. Also, the GCIV and Diamond Pro do not have the counters built into the rail. That is the only dislike I have of my GCIII. I don't like counters on the table. They also do not have big metallic name/brand plates on the rails either. All rails are smooth and flush. They have 1" slate, and GOOD slate. Not all slate is made equal. I've seem some lesser local brands, and their slate is horrible. Stick with the big names.
So - I'd definately search for one of these. Do not compromise and get a lesser table because you figure you can get a quality light in the deal also. Go all out and get the best table you can possibly afford. Later on you can get a nice light, or you can even build one that will be every bit as bright and functional as far as not making shadows under the rails - if you're looking to save money. Lights can always come along - great tables do not.
Ball return is aweful. Now, ball return properly set up on a home table should be OK. I don't like it because it makes too much noise. Trust me, first time you hit a ball in a perfectly quiet home, you'll know what I mean. As you are in deep concentration, you don't want the THUD and CLANK sound of balls running through the return. That's mostly my opinion. I just like hearing my tip hitting the cue ball, the cueball hitting the object ball, the OB hitting a rail or a pocket (and the sound of the balls rolling on the cloth). It is quick and it is over.
If you practice by drilling all around in different pockets, set up shots, and walk around and pull balls out and run them - ball return is bad. It is easier to walk around and grab them for that practice drill, or as you change shots or drills, and easier than having to walk to the end and bending over and trying to scatter them or having to roll them to one corner where you might stash them while you shoot a particular shot over and over 15 times.
If you practice by racking the balls, breaking them, then running them - ball return is better as you don't have to collect them. Also, if you practice by playing straight pool by yourself and you can frequently run a decent amount of balls - ball return is good.
Your budget is listed at $4000. That should be plenty fine for finding yourself a GCIV or a Diamond Professional in good to great shape. I don't believe any other brand or type of table plays as well or offers the same conditions - these are the best. At that price, you should be able to get a barely used one which would be like buying a brand new one but not paying the premium. Some others might find you deals where you might be able to up that budget $500 and find one of these tables NEW.
Here's a GCIV on Ebay, new, for $4,500.
http://cgi.ebay.com/NEW-BRUNSWICK-GOLD-CROWN-IV-POOL-TABLE_W0QQitemZ150004795958QQihZ005QQcategoryZ21213QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
When you get your table, you will be spoiled. The new cloth, lively rails, and level surface will make playing at the pool hall less fun at first. You'll be able to actually slow roll a safety that you'd never attempt at the pool hall because of fear of curving. Having a nice new set of Aramith Super Pro's will also spoil. Your set will have 1-15 all the same size, not 1-9 more worn out than 10-15 which causes racking issue and gaps. Your wooden rack will also be in shape too. Table will rack easy and perfectly - no Sardo needed. IF the spot was marked correctly, and the rack is not tilted when you rack - expect the wing ball to go in A LOT in a rack of 9-ball. Being clean, they will not induce as much THROW as dull or filthy balls at the pool hall. You might have avoided certain types of multiple rail position shots in at the pool hall due to heavily worn out and soiled cloth as well as half-way dead rails - but at home, you'll be able to execute some really cool shots. This actually gives you an opportunity to learn parts of the game that just aren't possible in certain pool halls due to the tables. Practicing certain shots on bad conditions makes it so difficult to gauge real performance that the shot becomes trivial and then annoying.
The best part of it all, is being able to shoot in your boxer shorts, listening to music you like, with no smoke around. Ahhh the luxury! Sorry, went off on a tangent there - I'm excited for you!