Medium belts sounds perfect...... unless you're waist is actually smaller than 34".
If your waist fluctuates to smaller sizes, I'd recommend getting a set of small belts.
The medium belts will work on people smaller than 34" but you're risking bottoming out the belts.... i.e. no more webbing to tighten the belt with a huge/heavy load.
Get the smalls.... I'm a 33" to 34" and I always use smalls.....
