There are alot of considerations that you have to take into account with pedal boxes or assemblies and like anything else your decision will have potential consequences that may steer you away from one layout or another. Based upon my experience (I have a Tilton 900-Series firewall mount pedal assembly in the OLC '67) I can offer the following thoughts and observations:
Manufacturers - top 3:
In all reality the three are probably tied as they all offer a top shelf system but I ranked them that way because (a) I have seen and used the Tilton system, (b) the AP pedal box is a proven product (primarily overseas) but I had very little success sourcing in in NA, and (c) the Brembo unit is quite new and I have not had an opportunity to see it myself. These are also probably the three most expensive offerings on the market but you did say performance over price and these three are used in top tier motorsports around the world.
Location and Mount
There are definately pro's and con's to both layouts, what I found was:
Floor Mount
Pros:
- More commonly available as a 3-pedal assembly
- More flexibility with reservoir mounting locations
- Easier overall plumbing
Cons:
- Camaro toe panel forces choice between fabrication and seat mount location
- Your pedals are where they are and you have to be comfortable with them
- You are going to have plumbing in the car and will need to consider routing outside of the car as well
- Need to think about steering column
Firewall Mount
Pros:
- Pedals will be located in essentially stock location
- Can use stock gas pedal or drive by wire (with 2-pedal boxes)
- You have a little more flexibility on location and layout
- Stock seating location is maintained
Cons:
- More commonly 2-pedal vs 3-pedal
- Can't use stock steering column (can be overcome - thank you Ididit)
- Reservoir mounting and plumbing requires more thought
- Drivers side valve cover
(can be overcome)
- Will require reinforcement of firewall and (recommended) tie to cage
2-Pedal vs 3-Pedal
Entirely up to you but you may be limited depending on your choice of firewall or floor mount. One advantage of the 2-pedal box is it allows you more choices with your gas pedal and location of the pedals themselves. On the Tilton assembly you can move the pedal pads relative to the arms to fine tune for fat feet. In my case I am using a locar gas pedal and am having a custom pad machined to optimum heel toe comfort. You could also buy a mono heel toe pedal cover.
One other consideration that you could have (and this would depend on you dash/gauge layout) would be the use of a through firewall or reverse overhung design with a firewall mound)
Thats knid of a quick summary. If you have any specific quesions or want more details just let me know.