Garmin Nuvi 350 (in pocket) + Etymotic 6i (in ears)
I've been pleased with the Garmin Nuvi 350 so far. I set it on the tank to let it acquire satellites while I put on my helmet and such, then put it in my front jacket pocket where it gets degraded (but acceptable) reception. The speaker isn't loud enough to hear over my K1200RS, so I plug in my Etymotic 6i earphones. I can live without seeing the screen while I'm driving.
The only flaw I've found with the Nuvi unit so far is the yellow pages stuff is out of date.
GPS on me, not attached to one of my bikes, so I can use it in rental cars when I travel.
Probably safer not to see screen while driving.
Etymotic earphones passively block most engine noise.
Nuvi 350 also has MP3 player -- interrupts music to give directions, then resumes!
Sometimes touchscreen is touched unintentionally when Nuvi in jacket pocket.
Etymotics also block sound of nearby cars, especially when playing music.
Sometimes forget to upshift because Etymotics block engine noise.