Jmorris makes a good point. Just look at prices on eBay to learn why this is so. If you loaded just 1000 rounds on the Lee, the savings over commercial ammunition would pay for the Lee press and it would still be in near-new condition. What you got for it on eBay then would be gravy. You would, of course, keep the dies for the next press you tried out.
The Dillons take more time to pay for themselves, but their finish holds up better than Lee finishes, IME, so you could still have a nearly new looking press after, say, 5,000 rounds if you care for it, keep it clean and lubricate as directed, but you probably don't need to go that far. The lifetime warranty that transfers with Dillon presses keeps the value of them up even when they are not in pristine condition, as the new owner can always send them in for reconditioning, as described by Old454. So they are hard to lose money on.
The 550's manual indexing caused Dillon to rate it as faster than the Square Deal. They claim a coordinated human being can operate the manual index fast enough to beat the fully automatic machine. That never made sense to me. What I do like about manual indexing, though, is the ease of single-loading for load development and making initial die adjustments when setting up the dies on the tool head.