I consider the two themes in question to be the greatest instrumental rock songs in the history of video games (and I am open to debate on the subject). These themes represent a time when heroes were lone warriors against an entire horde. You felt as bad ass as the themes sound. However, much like the Highlander, "there can only be one." So which theme gets your vote? Lee Jackson's Grabbag or Sonic Mayhem's Quad Machine

And just in case someone bothers to vote and has no familiarity with these themes, or are perhaps confused because I failed to mention what games they come from...

Grabbag V.2
http://www.youtube.com/watch?v=lksnCIPau5U

Quad Machine
http://www.youtube.com/watch?v=Z6VpX-feA2M



****Addendum

On the suggestion of Herrorcman, I am adding E1M1 to the list. It is a classic FPS theme and is a rock instrumental. Please consider Bobby Prince's excellent track, "Hangar" a.k.a. "E1M1" when considering this informal poll.

E1M1
http://www.youtube.com/watch?v=oQs48dvebck

Aww, no Doom E1M1? I'd put that one up there in a heartbeat.

Anyway, despite loving both Quake 2 and Duke Nukem 3D, I prefer Grabbag to Quad Machine. It's just much more iconic. Whenever I hear it, it instantly puts me in a good "it's time to kick ass and chew bubble gum... and I'm all outta gum" mood, while Quad Machine doesn't really do anything for me other than "oh hey, a great track from Quake 2."

Edit: And that new version of Grabbag's good, but I personally like this one better: http://www.youtube.com/watch?v=jnHD-kngaUY

I prefer other versions over that one but Grabbag is actually something I listen to quite often! Would like to hear a cover of it by KillrBuckEye actually...

neither :P

Actually, I loved OC Remixes take on E1M1 for their "Dark Side of Phobos" concept album. And yes, that is a rather iconic theme, but it never quite got me in the mood to rush down on my foes, the same way that Grabbag does. Which for the record, is my favorite between the two themes I have listed. Still...maybe I should amend my thread to account for E1M1. It is a fantastic instrumental.

Personally, I don't think anyone's done Grabbag better than Megadeth.

I assume my last post already counts as a vote, but I still prefer Sonic Clang's version. I think it's closer to the original.

The title theme from Descent II is also pretty neat. Short but sweet. The music was on the disc as redbook audio, and I remember frequently popping it in my CD player just to listen to the music.

I agree this version is the best, but I also love the original midi.
As for the Duke Nukem Theme I liked Manhattan Project version the best:
http://www.youtube.com/watch?v=LHFeybMGEUs
Why choosing Quad Machine from Q2 soundtrack? There are better tracks such as:
http://www.youtube.com/watch?v=ALBKFB28E0M
http://www.youtube.com/watch?v=ptUXTca_zhg

My favourite of all above would be Descent into Cerberon but if I were to choose from the first 3 from the 1st post, I would go with E1M1, Sonic Clang version ;p

Edit: Forgot about Painkiller! That game also had awesome music pieces:
http://www.youtube.com/watch?v=4wQNzNOhWAc

You are more than welcome to vote. You are the first to vote for E1M1.

"Goin' Down the Fastway" in Rise of the Triad is the best song of the DOS-era of PC gaming.

It's definitely up there... except it doesn't fit the genre in question, which is "instrumental rock."

Both are awesome themes, but I'll go with Quad Machine.

Hmm, it's a tough choice between Grabbag and E1M1.

Speaking of Grabbag, the guy who made it is selling the audio cards he used on eBay, to fund his return to composing music: http://cgi.ebay.com/300565859197#ht_722wt_977

And apparently he didn't get a single penny from Megadeth's cover :(

As far as which song is better, I prefer the industrial sound of Quad Machine, though Grabbag is much more iconic.