I've owned one of the Ultra 24" fences for 12 years. About a year ago I purchased the LS/Super System to get the Wonder Fence, with its adjustable width opening and offset fence capability. I was going to upgrade my Ultra but it was too old to be cost-effective.
My contrast... The LS is "heavier-duty". On the Ultra the micro-adjust indicator is a weak point. I don't mean to imply that it's not well made but it's exposed to being hit and shattered. I've replaced two. The LS's base also better protects its main position indicator. The LS's micro-adjuster also has unlimited travel while the Ultra requires you to move the main body a few 32nds and back off the micro.
New models of either are supposed to accept the Wonder Fence, which you'll likely want to add at some time. When routing, I often "bury" most of my bit in the fence. Without the Wonder, you build a sacrificial fence; with it you spread the fence halves. To that it adds built-in dust collection (which you could build yourself, if you wish) and easy offsetting of the fence halves, for jointing.
I think you'd be very happy with either one!!
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