<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Do they make it difficult to actually cash in and use your earned miles - or is that relatively easy?</font>
If you are a member of the United Mileage Plus program, log in to the Mileage Plus portion of ual.com. You should see a link for "award travel" in the left-hand column. That link will take you to a screen where you can enter some dates and cities and see what a "saver" award will get you. You can find out from that how easy/difficult it is to get awards for various places/various times of year.