I agree that many issues that become frequent subjects in internet jeep forums are far less common than the tone of some posts would indicate. Prime examples are ECM/PCM issues in the 05-06 model years, "laughing monkey OPDM's, and "garbage" 42RLE transmissions.
Although there is no way to verify numbers, I'm sure that the number of TJ's that have been re-geared to 5.38 is relatively low and the number of those with post 5.38 re-gear vibrations is even lower than that. However, based on re-gear installation reports and the increasing number of 5.38 gear ratios listed in internet jeep profiles, and the fact that searches for posts describing post re-gear front end vibrations yield almost none that predate the release of of the thick cut 5.38 gear sets by Revolution Gear & Axle, every indication is that sales of 5.38 gear sets are brisk which in turn suggests that we may hear more vibration reports in the future.
I guess what I am saying is that as more people re-gear their TJ Rubicon Dana 44's to 5.38 gears the more vibration reports we are likely to hear and the more common manual hub conversions are likely to be among those like me who don't have the patience to chase those vibrations. Enough so to warrant asking whether manual hubs have been installed when someone boasts that they re-geared to 5.38 and have no vibrations whatsoever. I am told that a forum member has made just such a boast here. Ironically, if it is the individual I think it is, he does have manual hubs.
Manual hubs aren't for everyone. They are an expensive proposition and start one down the slippery slope to other modifications that would otherwise never be under consideration. But as I acknowledged at the outset of my quest for a resolution to the vibrations that became apparent after my re-gear - I don't have the patience to spend hours trying to dial the vibrations down to an acceptable level much less dial them out altogether, especially when manual hubs are a "sure fix."