Yeah, the Meshuggah song was a really heavy song. I love playing them because of the crazy rhythms that they use, which is a real challenge to wrap your mind around (the verse riff is 23/16 played over 4/4 timing and every 8 measures there is one beat of 1/16 to sync everything up, you actually have to ignore the drums to play it on time). The mediafire link was a cover of a lamb of god song that I did by myself, it was mostly a test of trying to add drums to my stuff.
This might be more along the lines of something you might like:
http://www.youtube.com/watch?v=zJ_9yOnLYvEThis is Closure from Opeth, its an acoustic song for the most part, I messed up a little bit, but overall its pretty nice.
If you want something heavier than that, but not as heavy as Meshuggah, than this might work
http://www.youtube.com/watch?v=up7kv7VBOPoThis is half of The Leper Affinity from Opeth, and has some pretty awesome guitar work in it. The intro is a lot heavier than the rest of the song.
Edit: 1:40+ is awesomeeeee.
As for one of my collabs, I know I have them somewhere buried in 2tb of stuff. Its a strange mix of folk and black metal and the vocals are pretty grating (since its black metal) but it was pretty interesting. Another one was a crazy attempt at power metal, but not retarded, more happy, upbeat sounding metal. That stuff was pretty awesome. And if I cant find any of them, than I can try to get a hold of the guys I worked on them with.
As for your song, I would have to hear it before I can give you a definitive answer, as I can play a wide range of styles. I havent written many solos, as I like to write fast counter rhythm parts instead of being super flashy. But, I can definitely give it a shot.