i've bought my last three bikes w/out a test ride, but i knew what i wanted and, very importantly, what size i needed. it's tough because no shop can carry every model out there. The poprad is a great bike if it fits your body and your purpose. does the shop have fit kit type set up where they can replicate the dimensions? I've done that for one bike and it was helpful, mostly in confirming the proper size.
test rides are great but far too often they limit your choices to a small number of candidates. since it's your first bike take some time and ride other bikes with similiar and different geometries and sizes. remeber top tube length is of prime importance lemonds run long in the top tube, so you may end up on a "smaller" size then some other manufacturers.