I wondered when Ben would show up...
I've used RCBS and Lee dies, and you know what? I like the Lee dies better. The RCBS die I had was fine (brand new set, came with a used gun) but I swapped it out for a Lee RGB set after using it for 1 day. I got more for the used RCBS set than the Lee RGB set cost new. The Lee set happened to FL size just a wee bit more accurately, and for a gun with a tight chamber, it made all the difference. I guess I had a RCBS set that was on the edge of spec.
Now, would I use Lee dies (or RCBS) if I was a benchrest shooter? Probably not, though I might try using a Lee collet neck sizing die, since a world 1000 yard record was set using one back in the 1990s. For hunting and casual target shooting? I get sub-moa loads from my Lee stuff. I've had nothing but great customer support from Lee as well. The extra $ I saved went downrange as bullets and powder. Is Lee for everyone? Nope. But let's dispense with the notion that it's a sub-standard choice.
Every reloading manufacturer has items that are best-in-class, and other items that are best avoided. For Lee, the Classic cast press, the collet NK dies, and the factory crimp dies (if you're into that) are known as excellent products. The Lee hand priming tools are great as well (if you prime off the press, as I prefer). The dinky little scale you get in the intro sets? Not a great choice. My press is an older RCBS (pre-rockchucker) model that I love - had I bought new I think I would have gone with the Lee CC, but I'm very happy with the RCBS. My scale is an older RCBS beam balance model (pre 5-0-5, very similar, made by Ohaus). Again, great product for the money.
I guess the point I'm trying to make is that slavish devotion to one brand or another is not a good idea - each manufacturer has good products on offer, and some not so good ones - and folks starting out should investigate their options and make informed choices. For those looking to start with the least cash outlay, Lee die sets are a great value, and they make great ammo.
And no, I have no affiliation with either company (or any reloading company for that matter). Just a guy who likes a good deal.