Every shop is a little different, but it would't hurt to ask them if they'd be willing to order one for you to test ride. Are there any other shops in area that are Specialized dealers? Maybe you could test ride a Pro at a different shop.

My LBS was willing to order my bike without a commitment from me to buy it, but it was a $1300 bike. If your LBS is not willing to do that, then test ride the Comp to get a feel for the geometry, frame and fit. The two bikes are identical in those aspects, right? If so, then the only difference is between the components and, perhaps most noticeably, the shifting. Maybe they have another Dura Ace equipped bike that you can try to a get a feel for the difference between 105 and Dura Ace components.

In my opinion, the most important things to focus on during a test ride is, first, whether the bike fits and, second, whether you like the ride quality of the frame. You should be able to figure that out for either bike by riding the Comp. If you like how the Comp brakes and shift, just picture yourself liking it even more with the Pro.

Also, you haven't mentioned in your posts whether you prefer to get a double or triple crank. I notice that the Comp is offered in either a standard double or triple, while the Pro comes with a compact double. Depending on what kind of gearing you want, that may be an important factor in your decision. I know it was a factor in mine. I have a hard enough time climbing with my triple. I'd never make it up the steep climbs we have in Indiana with a compact.

I know I've given my two cents on this already but in looking closely at the specs for both bikes, I have to say that the Pro is what I call a "whole lotta bike." I'm a total bike geek and completely understand the appeal of high-end bikes and components, but I think that the difference in price between the two bikes is just too much for the performance advantages that you would be getting with the Pro. I have no idea what your budget is and, if price isn't a factor, then knock yourself out with the Pro. Otherwise, I'd go with the Comp.