Need help.. $150 headphones, closed set, good bass, good soundstage

Nah, soundstage on the M50 is fine, especially for this price range, bass is great, very balanced headphone but you will really enjoy them, definitely comfortable enough for the gym (I do it sometimes but prefer my IEMs.) Great for gaming like BF3 sounds really realistic, will really perform great for any style of music. Get the coiled cable version though for sure.

I didn't really enjoy using my M50s for BF3. The bass was pretty heavy on it and it was hard to pick out details and positions. The mids are also slightly recessed, so there are definitely more balanced options for the price. The Audio Technica A700 supposedly has a very similar soundstage to the AD700s, and is a closed back phone. Since I don't actually own them, I can't really comment on the bass or build quality. The Brainwavz HM5s also supposedly have a good soundstage with a relatively neutral tone. Fostex T50RPs also get put up once in a while as a gaming recommendation. 

Personally, I would never use cans at the gym. They just get in the way too much, fall off too easily, and accumulate sweat. They aren't meant to be used for physical activity, so I'd recommend the IEM route.

The Pro550 is maybe a good choice (from reviews) but i don't have them. The pro650 is good too with these genres, relatively neutral for the Ultrasone line.

The srh750 has good bass quality, a large soundsatge, comfortable...

The HFi580 can be also a good choice, narrower soundstage but good punchy bass.

The HD380pro is also a choices to be considered for games/movies, good bass, big soundstage (but feel unnatural), clear mids and treble. The main problem is the huge clamping force, with my case, i have a headache within 1 hour.

The Pro 550's are pretty decent if you want a combination of bass and an ok soundstage. People have described them as having a "v-necked" sound which I think is pretty accurate. They have good bass, but also unexpectedly strong highs. I like that, as you can hear every detail for stuff like snare and hi-hats, or gunshots and footsteps, in your case. They are perfect for hip-hop and EDM as well. One warning: you probably won't want to wear them for more than 2 hours or so. The pad on the top is a little stiff.

There's a whole thread discussing the DJ-1 Pro (rebadged and slightly tweaked Pro-550) here: http://www.head-fi.org/t/536185/you-asked-for-it-you-got-it-ultrasone-dj1-pro-review/15#post_8051525

I haven't tried the Audio-Technica A700, but if it really is an AD-700 with less soundstage and more bass, it could be pretty nice. They also use the wing system which is amazingly comfortable.

What is Inception style music by the way? Like... a song within a song? :P

Edit: just saw you want to use them for the gym... all these headphones are pretty huge. You might want to consider some IEM's or on-ear headphones if you are going to be moving around a lot.

I'm just as lost looking for a set matching your needs minus the gym part lol

Have you checked out the Audio Technica ATH Pro700 MKII?

Im leaning towards a used D2000 but thats because I don't need portability as much.

FA-011. Just obtained them used, jesus christ.

Currently my best (I prefer them over my HD25, and my previous but now sold M50, DT770 Premium, and AD700).

Sound stage is great, bass is actually really deep and punchy, especially considering it's open. Mids are great, trebles I don't know cause I'm pretty sure I can't hear past 14khz. Comfortable (though if your ears stick out a bit like me, they might make the middle of your ear ache a bit after awhile).

I listen to everything from Dubstep / Drum & Bass to piano-dominated instrumentals and they sound great with ALL of them. Never heard bass so deep either for under $200.

And the bass is actually rumbly and really deep when called for, ex in Dubstep w/ Flux Pavillion's remixes / songs.

Only con though is if you buy them off GD-Audio new you're going to have to wait weeks.. I bought one off of them then I contacted moneybookers after 2 weeks after it said it was shipped, and they ended up refunding me a week after contacting them cause GD-Audio didn't contact them back.

Then a day or two later, I bought it used from a guy, he sent it in the morning, and then I received it the next day.