Serously? A bias ply swamper? Road manners? You can't discuss both in the same sentence! I don't think Interco actually makes a round tire! They kick ass off road, but aren't meant to be used on a true "street" vehicle...
My XJ is my DD.... meaning.... i drive from my house to my work (about 12 blocks), and home every day. On the weekends I usually drive it to wherever I will be wheeling, wheel it, and then drive it home. Those are the only road manners i care about. For actual road trips or even going to the grocery store, i drive the JK.
I dd'ed my xj 70 miles a day with 6" of lift and 35's. its not the DD anymore but I still plan on driving it cross country and where ever with the tons and 37s.
IMO, I'd say Swamper Q78s are the perfect tire for an XJ (or MJ in my case). I'd swap my new 36" SXs for another set of Qs. They are 35.5x11, ran at 5psi on an 8" wheel without beadlocks, tough as nails, and the thread depth is deeper than any other swamper. my 0.02