I really doubt a 2 way setup in the stock locations will give good imaging because the tweeter is in the mirror pod and the midbass at your hip. I would definately go with a 3 way setup to get the mids as far forward and up as possible. I would then narrow down 3 way setups to the one that has the lowest crossover between the mid and midbass so again to keep voices forward. I dont know of any inexpensive solutions. For my money, the best OEM location solution is the rather expensive Hybrid Audio drivers. While entailing a bit of work, some have fit the Hybrid 4" driver in the oem location and then the 8" driver in the midbass location. This way, you can run the mid all the way down to around 250hz without a problem and you keep the image forward.
Another option is to go 2 way with a custom door pod to put the midbass where it should be. Of course, this is a lot of work too.
Some people have used the Focal 3 way setup and have been happy, while others have pieced together less expensive combos in a more DIY way by picking raw drivers from such places as
www.madisound.com.
Sorry, but there is no easy solution. From the 3 brands you list, I have a personal preference for the Hertz lines, but to each his own. Good luck.
