Opted for the EZ-Vest since I weigh 110bs, height 5’4” Weights sit well on my shoulders. Recovering from an ankle surgery, started rucking with 2x5 lbs, then 15(5,10lbs) for 2 weeks, will be upping weight to 20lbs(10,10) next week. Have added shoulder strap paddings, bought on Amazon, definitely more comfortable and will need for 20lbs and up. Kensui saves my arthritic hands and gives a better zone 2 workout since I’m walking way slower than my usual speed. Also doing squats, lunges and step ups with said weights. Would recommend to anyone needing stronger muscles and denser bones.