My wife and I are going to Scotland as part of a church pilgrimage to Iona in August 2013.
We're going to go over about a week-10 days before the week in Iona to tour around Scotland.

I'm trying to convince her we ought to tour on a rental BMW rather than in a car (cage).
I welcome your feedback, pros and cons, experiences and suggestions about my current idea:

Ship our helmets, riding boots, and Darien Aerostitch suits via UPS to where we rent the bike.
Include a return shipping label in the box and ask the rental place to hang onto the box for us.
(http://rentamotorcycle.co.uk/ and http://scotlandbybike.com/motorcycle-hire/
appear to be two good places - feedback appreciated.)
Rent a F650GS or F800GT for two-up riding
(Side note: I have '74 R75/6 and '05 R1200RT - we've travelled/camped on both.
I'm thinking smaller roads, lower speed limits in Scotland that smaller bike will be fine.)

We're planning to concentrate on seeing the Highlands, Trossachs, Skye, and Islay while on our own.

Ride the train between Glasgow and Edinburgh before or after the motorcycle rental.
We meet our church group in Edinburgh, go to the Tatoo with them and then travel with them by train (and ferry) to Iona via Mull.

Any must ride roads or must see places?

Tips for travel in Scotland?

Thanks in advance for your suggestions.

Thanks in advance.