I think the Sonus pads work great with the UDM. Yellow, white and Red, also the DAS pads white, orange and blue. Also the Sonus polishes are great for first timers because they correct with very little marring. Autopia has a great package that gives you the UDM with the three pads and polishes that is very tough to beat. I have heard that there are corrections being made to the UDM since there have been a few of us that have had problems with our polishers.
But if the Flex is out of your budget, I would strongly suggest getting the sonus package because it will give you everything you need to get going on the truck. I believe that you also get a couple of MF's.
Once your done polishing then maybe go with Meg's 16 or the yellow carnauba. I think you will be very impressed.
Fergnation- also in INDY (well Fishers)