I get good results loading with LEE dies.
My .308 rifle build, based on a Savage Axis rifle I paid $250 for, gets 1/2" groups no problem at 100yds, IF I am doing my part. The trigger was upgraded, stock and barrel replaced. Even with the factory 20" barrel, I was getting sub moa with little effort, but with less consistency.
I think more importantly, adhering to proper loading techniques and attention to detail will get you further than just an expensive die.
IMO, to take advantage of an expensive die set, you need so much more equipment and knowledge/time spent than JUST the dies.
More expensive trimmers, neck turning equipment, primer pocket tools, annealing etc.
I get by with a $50 CTS trimmer, blow torch annealing etc.
Here is where you get what you pay for with LEE dies........
I use the neck sizing collet dies for precision bolt action.
They often do not provide the amount of neck tension that I want.
So I chucked my die's mandrel into my drill press and polished it with very fine sand paper until it was the diameter I wanted.
After doing that, it provided the neck tension I was after.
For loading .223, I use LEE dies. With my precision AR15 rifles, there is no problem achieving sub moa. Again, using proper loading techniques and adhering to good procedures, using quality reloading components etc.
I'm not telling you go out and buy LEE dies. I do because I am a cheap ass.
When I get into a new caliber, I always buy LEE dies with intentions of buying more expensive dies in the future, IF I end up liking the caliber and plan on shooting it for a long time in the future.
They end up working well enough for me, that I never end up upgrading.