Don't take this personally because you asked for opinions. I am sorry if you will not like what I have to say, because it is hard and honest, but well-intentioned.
Can only comment on the mp3 on the website.
This sounds like a typical garage demo recorded off a cheap tape deck. In general, this is hopeless. It will *never* mix right and sound professional, there are some obvious and unforgivable errors committed, there is a ton of background noise.
I'm confused to exactly what entailed the mixing process because there is no definition, no low end, no high end... just muddy tinniness. To put it into perspective, if you made this a hundred times better sounding it would still take years to reach the sonic quality of St. Anger. The guitars sound like 12" Peavey Bandits, the bass is only audible when the bassist screws up, the drums have the tone of wet cardboard and the guitar leads get lost in the shuffle.
Releasing this in any way shape or form is a bad move. It's unprofessional sounding. Even with vocals this would be bad. Nothing can save this recording.
In today's world of easily accessible and cheap quality recording there is ZERO excuse to sound like this as a finished product.
Do yourself a favor. Delete it and burn any remaining copies and call your local studio or invest about 3-4 grand in recording equipment.
But before you do that get a singer and write songs. This is not a song, it is a bunch of guys trying to show off fancy playing. There is no real arrangement, the piece goes nowhere, absolutely zero MELODY, and there is not a solid structure whatsoever. There is a limited audience for this type of material--and that audience consists of the musicians that played it, their wives and *maybe* their mothers.
Write strong solid songs. It doesn't matter if it's thrash, punk, jazz or country. The *SONG* sells. Just ask Metallica, because they didn't sell nearly 100 million albums because of technical wizardy and songs that had 50 different riffs and no melody.
I swear if it starts and stops to head off in a totally different direction one more time I'm going to start praying for my final death.
This is bad on all levels.
I hear some solid musicianship going on, now it just needs to be refined and disciplined to performing songs and recorded in a decent recording space, with decent equipment by a skilled professional.