This car is one of my many guilty pleasures. The Reatta, although half-assed and not very polished, is proof that GM really could produce something quite futuristic and eye-opening. This thing had a touch-screen in the interior in 1989, the first production car ever to feature this. It's also quite a good looking car; it's soft curves are very pleasing to the eyes, and its proportions are spot-on. It's oddly reminiscent of the Porsche 928. I'd even dare say that, despite this being much cheaper, it was a more alluring car than the Cadillac Allante which was offered at the same time.
I've posted this in another thread before, but in my opinion, the Buick Reatta was what spurred the Japanese personal luxury coupe. Although the Reatta was by no means a sales success, it seems evident that the Japanese really took note after the Reatta's debut. The Reatta introduced the idea of stuffing futuristic tech into an old-fashioned luxury coupe, and this is what spawned cars like the Mazda Eunos Cosmo, Toyota Soarer/Lexus SC, and to a lesser extent, the Subaru Extent. The Soarer and Cosmo share styling cues with the Reatta as well, having soft, graceful curves and a short wheelbase.
But in any event, Meh is the highest I can give it. It's still a half-assed unpolished, underpowered '80s GM car bought by old folks just like any other Buick. I'd reckon that the average person couldn't distinguish one of these from a Chrysler Lebaron convertible.