I own a Diva and a BH Speedrom (2010). Both are Ultegra SL, except that I put a Dura Ace crank on the Diva. The Speedrom listed for less than 1/2 of what the Diva lists for. The Speedrom is a "mens" bike with a compact geometry. The interesting thing is that despite the fact that it looks different than the Diva because the seat tube is much shorter and top tube is much more sloped, the geometry of the frame is almost identical. I love climbing on the Diva, but I've got to say that the BH has slightly more solid, predictable handling in descents. That could be the different wheelsets...who can say for sure? I am so impressed with my Speedrom (although the latest model is spec'ed down a bit in the frame and fork) that I would have to say the upgrade to the Cristal would have to be amazing. They're both good companies and great bikes. I think you would have a much easier time finding a good price on the Diva rather than the BH Cristal however.
FYI there are some smoking deals on 2008-2010 Divas on the Orbea website.