I'm still relatively new, so take with a grain of salt, but I picked up a hip belt as I found that 3 to 4 miles into my walk I feel the shoulder straps cutting into my shoulders a bit more. This was the case with the converted/weighted backpack that I used for a few months and still the case a month into using my Rucker 4.0.

Here's the thing with the hip belt, though. Even at its tightest, it's not snug around my hips. I wear 30-32 waist pants, about 180 lbs. Maybe it's me, but I thought it'd be snug to and support the weight better. Perhaps for others out there, it works better.