I've no experience with big desiccants so I can't speak to them. Most of my experience is with the Dritec 325's and they were great units.
I personally prefer the rapid drying that heat gives you, whether it's an E-TES or the TES trailer unit. The desiccants do an great job but it's still slower drying. Both can create the lower vapor pressure for faster evaporation but the heat drying done correctly is so much faster.
You could always start out with an E-TES or a
Phoenix Firebird and see what results are like to test the waters. These units can be used with existing equipment but will work better with the high temp dehumidifers.
Take a look at
Drieaz's new LGR 2800i, it looks like an awesome addition to your drying fleet plus they can work in the higher temps and have an attachment for ducting hot dry air beneath poly sheeting.