We have a couple of years old Garmin eTrex that I just put in the little coin holder on the left side of the steering wheel. I angle it so I can see the speed, as that is usually what I am checking. It has no trouble keeping its satelites from there, either. If I want the nav part of it, that is what the person in the passenger seat is for...!!!

 

I have a six year old Garmin Street Pilot III which normally sees seven satellites from its usual position on top of the dash up against the driver side A pillar and the windshield.
I also tried it on the center console near the shift lever. There I only see five satellites and at half the signal strength as the usual position. (I do have the moonroof.)

 

I bought my TCH from a broker in Toronto. On the way back from Ottawa, I just put my Nuvi 350 on the passenger seat and it worked fine. I have never mounted the Nuvi 350 since it works great just being in the car on the passenger seat or in the cup holder.

 

I've used the Proclip solution in two vehicles (03 PT Cruiser & 05 Tacoma xRunner). They worked very good for my TomTom gps devices. The mounts they make for the Camry look like they are positioned well and not getting in the way of anything on the dash.
They are pricey though. (Much more than crunchy PB)

I really like my TomTom 910 device. It has bluetooth and iPod integration as well as GPS. The thing I did not like about it is that it was not integrated with the car. I always had to worry about hiding it. I chose to go with the factory NAV in my new TCH.

I'll hang on to the TomTom and take it with me on business trips/rental cars. I can't live without NAV now.

 

I think you will like the ProClip. The TCH's knockout in the console is positioned nicely so you can easily keep the cable out of site.
I've got the factory NAV but am considering getting a Proclip for my iPod.