I do plan to mount a weatherproof GPS on the bent at some point.
I'm pretty cheap. I refused to buy the $30 mount to put my GPS on my bike. I used one of the refectors with an adjustable mount and broke off the reflective part. I made a mount out of wood with my scroll saw and dremel and attached it to the reflector mount. I put the GPS on it with industrial velcro.
Shortly after I made it, someone stole my bike and I haven't made another one yet.
The Garmin eTrex Legend is weatherproof and pretty acurate. You can usually find it on sale for $100.
I know how ya feel about the stolen bike. Been there, done that.
I'm far too short on spare time to make a mount to fit the bent. Easier to just buy one.
The Legend is what I was considering, although the Vista looks pretty sweet.