Ok it looks like you have mixed reviews... I spent the better part of a year doing research between 3 lifts:
1. Slee 4 Inch KIT
2. Frankies Off Road 3 Inch Kit
3. OME Heavy Lift with Rear Adjustable Panhard
Let me say first that all information you gather from "us" is arbitrary since every man has his own taste.
Having said that I believe I listed the 3 above lifts in terms of most expensive to least expensive. Slee's kit as you know is not cheap, but comes with the most hardware if you go for the entire kit. Frankies isn't much cheaper, but you get as much IIRC. OME comes in on the "cheap side" of that with their kit. The only reason I mention all this is because, IMO, you get what you pay for with these lifts.
Slee's lift IIRC uses progressive springs now in the front, which makes for a smoother ride. THIS HELPS. Although I don't MIND the ride of the OME, sometimes it's "bounciness" gets on my nerves. It does it's job very well, i.e. bearing great loads and lasting to tell the story, but it's a bit brutish. Slee's lift rides much better, I know because I've ridden in one of his trucks. Frankies also uses the progressives and I have heard great things about his lift.
Also, with the "cheaper" lifts like Ironman and OME, they don't come with a full compliment of accessory parts, like drop brackets, DC Driveshaft, etc. that make the truck ride as well as it can. Some people don't end up needing the DC driveshaft. Lucky them. I would say most people after 3 inches of lift do need one to get rid of the horrendous drive-line vibrations from the front driveshaft. Some people don't need the drop brackets, but my suspension creaks now like an old ship rocking in the sea. Some people don't see the need to get adjustable panhard rods because they don't care that their but kicks out while driving.
SORRY for being so long-winded, but here's my point. You may not "need" everything in the kit that Slee offers, but he offers it as KIT for a reason for all of it. If I could do it over again, I might has well have gotten the Slee lift, since I have since bought drop brackets and am considering a DC driveshaft.
PS- The OME Heavies are plenty to carry the load you speak of if you change your mind.