The Lyman M die and the RCBS equivalent expand the neck as well as flare the case and are a little better choice when you are looking for the very best accuracy in only one or two calibers. The cost does add up when you shoot a lot of stuff, and the Lee does bell anything perfectly.
Lyman also offers a powder measure adapter that comes with hollow expanders that works very well and eliminates a step in reloading. The expanders in that kit are aimed at pistol, but a little tinkering adapts it to .30 cal and .35 cal rifle.
There are no really bad choices.