I went through a similar debate when I was deciding on what progressive press to go with. The Hornady powder measure is very nice, and the 'inserts' are a quick, easy, and cheap way to change out for different loads, and keep your load settings in tact.
To answer your question, to my knowledge, you cannot use the Lee Powder Thru Expander dies with the Hornady powder measure. This is really too bad, as the LEE PTE is really a great die.
I ended up going with the Hornady, and they have their own powder through inserts that you can use with their powder measure. These are caliber specific (you buy one for each caliber you use). I've had mixed results with these inserts. They are not adjustable, and if you don't get the right flare/belling to your case for the bullet that you are using, then it does not work well. So, I ended up buying a universal (one size fits all calibers) after-market powder through insert for the Hornady measure. This insert works pretty well; you just adjust the caliber specific powder die/lower to the depth that bells the case the amount that you need. It's definitely not as easy and precise as the Lee PTE, but you can get it to work.
This being said, I actually still use the Lee powder dispenser/PTE setup on my Hornady LnL press (just use it in place of the Hornady powder measure). The Hornady powder measure is a very nice piece of equipment, but the Lee setup is really a great solution (perfect/adjustable case expansion, and accurate powder throws...). I understand that Dillon has the same limitations (I have friends with nice Dillon presses, and use Lee Powder measures...) as the Hornady powder measure, but I'll let someone else speak to that, as I have not used that equipment...
I really love my Hornady LnL, and would buy it again.
NRA Life Member
Last edited by dmar; 08-06-2010 at 08:11 PM.