I used them on this last trip to try a DeLorme inReach as well, before purchasing. I also used them a couple of years ago to rent some micro spikes before a spring Cactus to Clouds hike.
Both times I have used them, I've been very impressed. They have gotten the gear to me early, and it's been in good shape, and easy to return when I'm done. Prices are pretty reasonable. As with anything, if I was using the micro spikes all the time, it would be a better deal to purchase. In the case of the DeLorme, it was a great audition before dropping $500 on a unit I'd never tried.
I have never talked to Dallas on the phone as you have, but their site is easy to use and I've been pleased with my two experiences now.
As a side note, the DeLorme inReach will most certainly be on my list of new items to buy now. Having two-way communication was tremendous, not the mention the standard benefits of GPS and tracking technologies.