Yes, there is a big difference if you plan on wheeling it hard. If it's to be lightly used, you could probably go the cheaper route.
But be aware that at that lift height, you are probably also looking at adjusting your driveline angles w/ a Tcase mod & new driveshaft. Even done cheaply, that's another 200 bucks or so.
Another option is a lower lift + small lift shackles + 1" body lift mounts + fender trimming w/ TJ flares.
You'll also need to regear your axles for anything over 31" tires. I'm assuming you want to run 33's or larger w/ 4" lift.
It would be best if you thought long & hard about what you're actually going to do w/ it. Sure, 33's look cool & are needed on serious, rocky trails....but on the east coast, I've seen guys w/ 31s, lockers & good articulation wheel the hell outta their rigs.