Hey,
In my humble opinion, if you really believe you know what you are doing and have done your research then you should go ahead and do this.
If it works out good for you then you can post data to back up your point...
If it sounds like crap...you will have learned a lesson and (on the bright side) you still have excellent equipment that you can:
1) sell
2) re-use when you re-do your install.
No one here is going to be able to fully predict that outcome since they:
1) probably haven't tried this particular setup
2) probably haven't tried this particular setup in this particular car
So there you go, it's up to you now to prove your point and prove these folks wrong...