Getting around your comment on why a salesperson wouldn't know much about units that he/she DOESN'T sell (why would they?), opposing slides on shorter TTs are not that common. The Winnebago 27RBDS has opposing slides and has a 30' 7' box. However, it is not "rear living" but rather the more common "middle living."
Winnebago 2101DS TT & 2022 Chevy Silverado 1500 LTZ Z71, WindyNation 300 watt solar-Lossigy 200 AH Lithium battery. Prefer boondocking, USFS, COE, BLM, NPS, TVA, state camps. Bicyclist. 14 yr. Army -11B40 then 11A - (MOS 1542 & 1560) IOBC & IOAC grad