I shimmed the rails on mine along with the nut-cage mod.
Our vacation rides...
Me + Wife = 400 lbs (I won't say what the ratio is)
Saddle bags loaded to the top (10-20 lbs per)
Uni-Go trailer loaded to the top with luggage (50+ lbs tongue weight)
No issues with nut-cage mod and shimmed rails. Both are easy to do. May as well get it done while you have the wheel off.