We also have a Sunseeker (GTS 2430) and we also have the wedge mattress. At home we have a sleep number mattress and keep both sides at 100. Yes, we like our mattress firm! The RV mattress does feel firmer than our home sleep number. Not sure where to find one softer. Maybe a pillow top?
Marilyn w/ Joe, 2016 Class C Sunseeker 2430 SF, often pulling a Ranger bass boat. Traveling with Trigger
Smudge & Gizmo are waiting at the Rainbow Bridge