For Budget Buys and still have something decent...
I'd go with G&G Sportlines. It's the same internals as their metal bodied versions, just has a plastic/fiber body ( It's way tough stuff! ).
My second down the list I'd get .. I'd skip anything with Echo-1 stamped on it, and get the same exact AEG in a Jing Gong ( Golden Bow). JG has really stepped up their quality standards, and are a bit cheaper than Echo-1 which is more or less just a "rebrand" of JG. E-1's do have a better instruction manual, I'll give it that much.
These are the AEGs that will give ya best bang for your buck, and will last you long enough to afford a nice ICS/Olympic Arms or KWA all metal competition grade AEG and all the extras to go with it... and still let ya play while saving up.
Both shooting over 330 FPS with a .25 BB consistently stock. We chrono'd my JG G36 Stock at Sogo's with a .25 averaged 375 FPS... on a 8.4 battery.

<<<To Hot for CQB, way awesome for field.
( Now.. here's a BIG misconception most people have in FPS in regards to AEGs... 380 FPS isn't
always better than an AEG that shoots say... 330 FPS. Speed doesn't always equal distance, and it doesn't factor in accuracy in the least bit.
There are too many factors regarding BB velocity to mention of exactly "why" FPS is mis-leading... but any real experienced airsoft players can show you the difference in a finely tuned AEG with lower FPS, than a run-of-the-mill higher FPS AEGs that aren't tuned up.
Slap a tight bore in, new piston, hop up , bucking, perfectly grease gears, shim the mech box, ect... and use HIGH QUALITY BBs.... accuracy and distance improves , even at lower FPS out-put. Really you don't have to do all that to a stock AEG most the time. But certain things can improve performance of ANY AEG.)
Now if you go with a 150-200 dollar AEG , you will eventually want to buy a higher end AEG. After your first ( even if it's a superdeliciousuberawesomething! ), it's addictive a bit to get other models, better quality, higher priced AEGs.
But... even though I usually tell folks just save up and buy a G&G all metal at least... , I do think it's important to be able to play airsoft, and find out what you like and you don't like about certain things.
Like me... I know now, I don't like AK models. I never really liked the looks of them in the first place ( except the Dragonov, which just looks intimidating for a sniping rifle! ) , and I've found I don't like the length of them , even the spetnaz and shorter CQB models... are still a bit to long for my frame and comfortableness.
I got a G36... now, I love this AEG! I wanted something different than an AR/M16/M4 when I got it... because I was in the army , and was kinda sick of looking at them. But I've found, it has it's quirks too.
Less accessory options , especially when comparing prices. Most modern mag pouches fit the mags to tight. Looking back, I shoulda just got the M4A1 ... but I'm glad I tried the g36 out. I love playing with it when I get the opportunity to.
Sig 552... now this was a 5 dollar bone-yard find, which I can use in Sogo's because it shoots under 300 FPS stock. It's a first generation JG SIG, meaning it has a craptastic plastic gear box in it... but , it did allow me to figure out I like wielding smaller style AEGs and SMGs. ( The latest JG SIG 552s are much, much better than the one I have. )
What you want to keep in mind when buying, is upgrades and replacement parts..if they are available or not for your brand/model. Also, any aftermarket parts you want should be attainable for what you are buying. Commonly, M4/M16 variants have the most in both those departments.
I've been playing a good while now, and still myself have yet to buy a full out High End AEG. I'm Going to before the next Ball Drop, or OK Invasion events... probably a KWA M4. Until I go to a big event though... I really don't need one , I do just fine with my Clones, and have no real complaints about them. And you can upgrade most of them too.
The bottom line is, like stated above... getting a mid-grade gun, like E-1 or JG, you get a battery, charger ( not the best but can get by until you get a smart charger. ) , and high cap mag ( High caps aren't very expensive at all for extras.) ... can play right out of the box.
It leaves ya some money room for decent eye protection, Tac vest, plate carrier, Hydration system, mag pouches, BDUs , and BBs and other little extras you'd like. Maybe even enough for a sidearm if you look in the right places.
Crud, it's late and I fear I rambled on and on... sorry about that.
If a don't have a budget... by a KWA or Olympic Arms.
If Money isn't any Issue... Buy Celcius or Systema.
If ya just want to blow 3 grand plus... buy that Mini-Gun.. lol! ( I sooo want one just to shoot it! )
But if on a budget... G&G makes excellent AEGs , but you will need to buy a battery for it.
Then E-1/JG are budget friendly, play right out of the box.
( Personally, I have no experience with CYMA or D-BOYS , so I can't say about them, but I don't think I'd waste my money on them. )
Personal experience... Classic Army and TMs are not worth the money. CA because of inferior internals , even compared to the E-1/JG lines. Also you gotta watch their after-market parts because many don't fit other brands well if at all.
TMs are nice guns, but it's very expensive to upgrade to US based FPS standards. But, they don't break down or wear out very fast for sure!
Any other brands.. I can't say. No experience with them personally.
But other than my very long winded re-ply.. I hope this helps a bit in any case.