If you saw the cheap Lee and the Rockchucker side-by-side, you'd laugh.
Here are a few things off the top of my head:
- The Rockchucker has a larger diameter ram
- The Rockchucker's ram is dead-center with respect to the die hole (my Lee wasn't)
- The Rockchucker's ram has zero side play (you could wiggle the Lee's ram)
- The Rockchucker frame is thick cast iron. I won't deflect under load
- It will be several lifetimes before the cast iron frame of the Rockchucker wears enough to cause side play in the ram. The ram on Lee press had a noticeable increase in side play after only a few thousand rounds
- The Rockchucker's base allows you to mount it with 3/8" diameter bolts and it has a wide footprint that spreads the load out on your bench during heavy sizing operations. The Lee's footprint is tiny, and you attach it to the bench with 1/4" bolts. I literally broke it off my workbench while forming cases.
- The linkages on the RCBS are heavy cast iron. Lee uses sheetmetal.
- The stop (in other words, the part of the machine that determines when the ram is all the way up) on the RCBS is a pair of large surface area lugs (one on each side of the press) that stop against the thick cast iron linkages. Top is top - you can jump up and down on the handle and the ram won't go up any higher. The cheap Lee has a small cast aluminum button that hits the sheetmetal linkage. If you push a little harder, the ram goes up higher. This will cause you to set back the shoulders on your cases by varying amounts. If you push too hard, you'll break the button right off.
- The Lee will send spent primers all over your shop.
The reason why people buy the Rockchucker at 4 times the price is that it's about 100 times better.
Just buy a good press. When you think about it, the cost of the press is not that much when you consider all of the other equipment you need to get. Why skimp on the piece of equipment that is used more than any other, and that will be a major contributing factor in the quality of your ammo?
Also, the only rifle rounds I crimp are ones that will be used in a rifle with a tube magazine, or very heavy recoiling rounds that will be fired in a repeater.
I don't crimp any of my .223 (cannelure or not) - even the stuff that I fire in my machine gun.