I'd say 125# is not alot to worry about. Even the 537 is a
light tongue
weight for a 6,000# trailer.
Were these both the 23' model? Were the tongues at the same length setting? Did they both have the same size LP bottles and filled to the same? Levels in waste & water tanks? There are lots of variables that could effect the tongue weights.
The normal range for tongue
weight would be 10-15% with traditional trailers for stability. For some reason the Olivers run much lighter, but have much more stable towing dyanamics. Part of it may be the lower center of gravity, part of it may be the suspension setup and the
axle positions.