Follow up question:
What's the budget for your (woodland use) AEG?
Do you intend to customize your kit? If so, how?
Mmmkay I'll try to give some tips and hints, but please do take the following with a grain of salt. Any objections/comments are welcome.
Please take note that I'm assuming the following:
1. You dig HKs.
2. As such, you dislike AKs

3. You are looking for a carbine-length weapon.
4. You're relatively new to AEGs, and you aren't familiar with the innards of gearboxes.
5. Due to this, you want something that works right out of the box.
6. And of course, you want something that's durable, reliable and beat-the-enemy-to-death-and-leave-no-scratches-able.
7. You want something with a fair number of aftermarket parts.
First off, I'd like to note that the biggest manufacturer of AEGs here in Japan is Tokyo Marui. They gave birth to AEGs, and they continue to have a dominant position in the Japanese market. TM AEGs work right out of the box, are completely within the legal limits, and are usually highly reliable. Most AEGs sold in stores here are TM.
I'd also like to mention that I'm not as familiar with overseas manufacturers as other TKO members, as I started airsofting in Japan.
Rule of thumb: Most reliable AEGs have a version 3 gearbox design.
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The following is a quick run-down of AEGs that you (IMHO) may be interested in:
TM M4 SOPMOD: TM's M4 SOPMOD with simulated recoil is the manifestation of "what sex should be like". It's amazing. I'm lead to believe that quite a few TKO members have purchased this wonder-tastic piece of kit. The M4 SOPMOD is quite new and has only a few aftermarket parts in regards of internals, but there is a plethora of external aftermarket parts.
G36 series: TM's G36c is a reliable piece of kit with rails everywhere for those who like to pile on accessories as if each addition ups their sex appeal (It does, in fact). Click
here for HK pron. STAR, a Hong Kong manufacturer sells many G36 variants (C,K,E) with a more durable, realistic material for the externals. STAR internals have a bad rep though, so internals should be bought separately. Version 3 mechbox, many aftermarket parts.
TM SIG series: Unpopular due to a lack of aftermarket parts. Burst fire is unreliable. Version 3 mechbox.
Old TM M4/M16 series: Most TM M4/M16 series prior to the latest M4 SOPMOD are largely made of fragile plastic, with a very fragile neck assembly which often leads to cracks in the externals in the hands of more aggressive players. Lots of tinkering is necessary to make these a reliable, durable weapon. Version 2 mechbox, gazillions of aftermarket parts.
TM P90: Issue with magazine feed. Unpopular due to unreliability and lack of aftermarket parts. Proprietary mechbox.
KSC HK33: Avoid them like the plague! They have serious reliability issues. It's fun shooting them though.... Aftermarket parts are slim to none.
STAR UMP: Durable, realistic material for the externals. STAR internals have a bad rep though, so internals should be bought separately. Version 3 mechbox.
That's about it for now.
Edit: Please don't kill me if I've just insulted your favorite AEG

Instead, show some love for your kit by presenting it's pros!