I have both. Biggest ergonomic difference is that the transplate harness shoulder straps anchor to waistbelt with angled slides that you can adjust as opposed to the deluxe harness, where the shoulder straps anchor on the plate, where they are threaded through the plate like a normal hogarthian rig. If you are a big guy or have shoulder issues, the transplate harness helps a bit more than the deluxe in donning, particularly in a drysuit because the lower shoulder anchors can be moved more towards the front.
Otherwise, I prefer the deluxe because it is cleaner and gives a little more room, but without the QD buckles, belt slides etc. The deluxe falls between the hogarthian model and the transplate and just adds transition rings and a sternum strap
I also preferred the transplate, if you go that route, without the pads, which don't make much difference and actually make the rig more cumbersome.
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