I put 28 tires on my new build, anticipating the greater comfort. But, I have to say that I'm disappointed. When I switched from 23s to 25s on my other bikes, the increase in comfort was astounding! "Whoa! I'll never use 23s again. And, 'they' say that there is no increase in rolling resistance between 23s and 25s." So, on the new bike, since there is room, I went with 28s, expecting another incremental increase in isolation from expansion joints in the roads.
After getting two flats in two weeks, one of which resulted in having to make the "call of shame" because a tire iron broke and I couldn't remove the tire, I'm dumping the nearly new 28s and putting on a set of 25s, (Continental Gatorskins). I've had good luck with Gatorskins. Not the most lightweight, but plenty tough. Carrying an extra 25 pounds around the middle, I'm not too concerned about saving a half a pound by running lighter, and more fragile, tires.