GPS: Zumo 450 vs. TomTom Rider 2

[NeilS]

I've decided it's getting to be time for a GPS upgrade, and I'm wondering if anyone here has seen the Zumo and Rider side-by-side.

I'm mainly interested in display visibility under various lighting conditions, ease-of-use, security of the mounting arrangement, weather resistance, and access to points of interest. I'd also like to be able to pre-plan a route on my computer (a Mac, but that might be asking for too much) and downloading it to the GPS.

I don't care about spoken directions, cute "3-D" display modes, XM/Sirius, Bluetooth, MP3, or the GPS working with my cell phone.

Any input will be appreciated.