Phil
I prefer to gather more information before determining it's unnecessary. I really have no idea what it would cost and haven't yet been able to verify if there's a benefit or a downside. But the idea of being able to look at a sight glass daily or after every trip vs having to remove the wheels and hubs to know if my bearings have sufficient lubrication sure sounds appealing. This is not a case of 'mine is better than yours' because I don't have them, nor is it a case of buying an add-on just for the sake of it. I'm just trying to figure out if it's worth making the change.
Some changes/upgrades I've made to our coach have been very definite improvements and not just because I made or paid for the changes. Some I've yet to make, such as one or two slide-out trays and a tire pressure monitoring system, will also be worth the money. Other "improvements" I've passed on for one reason or another. I don't make changes for the sake of it.
Because we bought the coach off a dealer's lot rather than order it, we were somewhat restricted in factory-installed options. As I hear about after-market alternatives to the options we didn't get, I like to evaluate them and ask for input from others. Your negative vote on the oil baths is noted, although it's not clear if you have an informed reason for it. If so, I'd sure like to hear it so it can help influence my thinking.