I got a set of climbing specific wheels and wanted a cassette that would leverage that even further. The 32-11 was a good call. I really don't use the 32 that often (most climbs are fine with the 30) but when you hit a wall and need just a little more leverage and a little more confidence, the 32 is nice to have. I was worried about chain length because my other wheelset has a 30-11, but I have had no problem. If I was moving from a 28 to a 32, I'd probably need an extra link or two, but the 30-32 switch has performed fine on an Ultergra Di2 longcage derailleur.
The Ultegra cassette has always been the best balance of price and performance. With the release of the 8000 series comes the new 11-30 cassette, which I really loved for cyclocross. Having the 30t was nice to have on steep courses over the 28 but only a little bit heavier.