I would have thought 27 inch would be too 'small' for curved screen. I see curved screen being better where it's close and takes you entire field of vision. Since the distance to the screen is short, the 34 inch monitor would do this nicely. That's not to say the 27 inch version isn't any good, just that the curvyness may be a bit of a distraction if it doesn't occupy your field of vision. A screen further away, like a TV screen, may be okay curved even if it didn't fill your field of vision, but that's different.

I've just read this post from a flat 27" screen and it seems that there is no need for any curvature needed. Another problem with curved screens is that you need stronger pixel separation to avoid back light bleed, which may effectively make flat screens superior in some regards. Well, curved screen makes the surface a little more perpendicular to your eyes direction, but is it really a problem with IPS/VA/PLS panels? I've just performed a simple test - I moved my head to the right, so I was looking at the right edge from perpendicular direction, and the color shift was visible on the left side (Dell U2713H). When I put my sight to around 1/4 monitor width, both edges still look ok, but farther from that point it might be not the best for color-critical work (still ok for color-accuracy-important-but-not-critical stuff). So if I had super-wide 54" monitor with the same height, the color shift would be visible around the edges, and in general sides in the screen with height of 27" one, but widened to over 38" might not be accurate in terms of color reproduction.