I have a 1999 XJ with OME suspension. 934 coils in front, the light duty leaf packs with 1 OME add-a-leaf in each in the rear, and the long travel NitroCharger Sport shocks. 31" tires currently but the next set will be 245/75/16 Duratracs most likely. I love it. I had a 1996 XJ before this one with Rubicon Express 3.5" Superride and 2 different sets of mediocre shocks. I'm not saying the RE was bad, but I'm much happier with the OME set up for my needs. The RE rode MUCH stiffer than the OME I have now....granted I had crappy shocks and no armor for added weight on the 1996. My current 1999 also has no armor or bumpers, but I do plan on bumpers and maybe some armor at some point. The OME is firmer than stock but it definitely rides better/softer in my experience than my RE set up did. As mentioned, the RE also sat up much higher than 3.5". It was probably close to 5" in the back. I haven't measured the OME in awhile but it was right in the 3" ballpark at last measuring. Most of my driving is unfortunately highway/city, but it does see some dirt and National Forrest roads/trails, and the beach a couple times a year if I'm lucky. Overall, I'm definitely happy with the OME, and would certainly buy an OME set up again.
My wife has a 2001 XJ and I/we have OME plans for hers too. Hers has higher mileage and is a little rougher than mine, so I'm thinking spacer in front, OME rear springs, OME shocks, a little fender trimming, and 33x9.50x15 BFG All Terrains if I can find them. We'll see. I got my 1999 from a family friend of the wife's all stock, just under 60K miles, no rust, never wrecked, second owner, originally came from out west....and the previous owner told me it was headed to cash for clunkers if I hadn't bought it. Appalling. The only option it doesn't have, that I wish it did, is the Chrysler rear end. I haven't had any issues with the D35 thus far, plus it has the limited slip (which my 1996 with Chrysler rear didn't), so its good enough for now. Still want to put the Chrysler rear in it if I can find one with decent milage on it. Shortly after buying it however, the front D30 did eat itself on the highway. Between me, my parents, and sisters, we've had 5-6 XJ's and I've never seen that happen. I had a junkyard high pinion D30 put in it and the only things it has needed since have been an oil pressure sensor ($50) and a power window regulator (junkyard $30) aside from oil changes. It needs a water pump, which I have, but just need to get time. I also have a Advanced Adapters SYE for it but haven't gotten around to having it put in yet. There are some minor/moderate vibes at 50-60 MPH and up ,but not terrible. It's got 1 or 2 degree shims in back, which helped. Still want to have the SYE put in though. It's at 111,000 miles currently and I'm trying to keep it fresh as long as possible. My 1996 was taken off the road at 250,000ish miles but the motor still ran fine. It needed a clutch and the roof had developed a nasty rust patch that leaked in the rain. I just couldn't pass up the 1999.
Sorry for the ramble, hope the OME info helps.