Powerful Pete said:
Good to hear oldbobcat, I had heard very negative things about CSTs (only good as a trainer tire).... always good to hear the other point of view.
I heard recently about tests that have been done for pain relievers, and the same pain reliever works better if the person taking them paid more for the drug.
I strongly suspect that the same sort of effect takes place for bike tires. The less expensive tires would probably do fine for most people.
I am not an elite rider, but I have never noticed a difference between tires... other than the fact that I like some sort of armored tire to reduce flats... and I admit that this could be partly psychological too.
My opinion on tires is probably invald since I have never paid more than $25 for a bike tire.
As far as the original question about maximum pressure... If you are a heavier rider, it is actually suggested that you ride at the maximum pressure in order to prevent snakebite (or pinch) flats. If you ask the average bike elitist, they will actually suggest riding at (or slightly above) the maximum pressure for lower rolling resistance, although I have read that some tests show that this does not always result in lower rolling resistance. Also, there is a margin between the maximum pressure and the pressure where failure will happen, so if you want to go higher, don't hesitate to use the maximum pressure. Maximum in almost any realm is not the absolute maximum, it is the maximum limit for safety.
I have no specific information, but a tire marked at 110 psi would probably work fine under ideal smooth conditions up to like 150 PSI... so don't worry about 110...
In the inverse, if you don't ever hit bumps that cause pinch flats, then you are fine running pressure below the maximum, and probably have a more comfortable ride. On a smaller tire you will probably need to run a higher pressure than you do on a 32, but do whatever works for you.
Also, check your rim width because if you are at near the minimum size for your current rim, you will have a higher likelihood of problems if you go too small... However, the chart on the late Sheldon Brown's site shows that all rim widths that are Ok for 32 should be fine with 28.
http://www.sheldonbrown.com/tire_sizing.html
He also discusses presure other tire issues here:
http://www.sheldonbrown.com/tires.html