The powder thru dies are a "must have" on my bench. Lee definitely is ahead of the others offering this as a standard in their die sets. The shell holder is another plus for sure. I use a turrent and mount RCBS Uniflows on the powder thru.
Again I prefer Lyman's powder thru...it comes with the multi stage expander for 7 different calibers and two different length drop stems. They are tall and no adapter is needed to raise the powder measure to clear other dies. Fits most powder measures without an adapter. The Lyman lets you upgrade other die sets without buying addional powder thrus. The downside is you have to change expander calibers (2-3 minutes) and adjust the die between caliber changes. If Lee had the multi stage expander I would consider buying their powder thru die...but they don't. Its another example of paying more and getting more with the Lyman.
Something I didn't post earlier is the die knurling. Lee is the only die mfg I can think of that doesn't do it (-$). Pet peeve for me but others may relate. When I was a single stage reloader and changing dies often, the dies without knurling aggrevated me because at times would slip out of my hand or make adjusting just a little more tedious. Not really an issue with my turrent dies that stay put, but it bothered me enough to appreciate the non slip feature of knurling. I've never see anyone post about this so maybe I'm the only one on the planet who has dropped a slippery die and bounced it off the shop floor.
I give Hornady the thumbs up for ease of adjusting...wrench flats instead of nuts.