I've been using DynaBeads on my trailer tires for a number of years and have had perfect results.
My approach is to first get the tires balanced when buying them new. Then, when I get the new tires home I bleed off the air and remove the valve stems so I can insert the proper amount of DynaBeads according to the tire size. It takes about five ounces for my trailer tires, maybe six or eight ounces for my larger truck tires. Then I replace the valve stems, air up the tires and forget about them until the next tire change.
If I have a flat, I put a plug in the tire while it's still on the rim. I've never had any problems with the beads clumping around the sticky plug or anything else. The tires I have plugged have been as balanced as ever. Ten minutes for inserting the plug, a couple of minutes for adding the air, and I'm back "on the road again" singing along with Willie.
When I'm ready for new tires, I slice open the old tires at the sidewall, remove the DynaBeads and reuse them for the next set of new tires. I have found that the "used" DynaBeads are always in great shape after many miles and years of use. They are made of a ceramic material that's hardy, corrosion proof and do not absorb moisture from wet air pumped into the tires.
One time when I returned from buying new mud-grip tires for my Jeep I found one of the brand new, newly installed weights had already fallen off. Rather than return to the tire store, I simply placed the proper amount of DynaBeads in my tires and found no problems with vibrations from any of the four corners.
So, I like them, in case you're wondering. :-)