Which One Should I Chose?

I am looking for a PDA with internal bluetooth, wifi and IR. It must have a CF slot and a 4-5 inch touch screen. I know this fits about a billion devices but most are a small fortune and consider i am going to be moding this device it should be as inexpesive as possible.

One device i was thinking that might work is the HP IPAQ HX4705. Would this work? Is there a device that would work better?

What i plan on doing to this PDA is to connect a 120GB 2.5" HDD via the CF slot and adding a larger Li-poly or Li-ion battery to support it. i would also like to be able to have it look more like a gps device with only the screen shoing and any need buttons along the frame.

I know it is possible to connect the HDD via the CF slot but i don't know if i will be able to put a large enough battery on the PDA to support the HDD, and not make it a monster. Also i have little experience with Linux and would like suggestions as to what distro i could use on the HDD that would be specifically for a handheld use. One more quick question. Can i do a dual boot sort of thing with the default os on the handheld and linux on the HDD? If this is possible then how would a access info on the HDD when in the default os? Would i have to use a swap file thing?

If anyone knows of a device that is fairly inexpensive and ALSO has GSM or GPS that would be awsome.

Thanks.

Poohbarr