I have been using zippered waders for a long time.
Some random thoughts:
1)when putting them on or off,be careful not to spread your knees too far,as it might compromise the zipper
2)to the best of my knowledge,all zippered waders now,regardless of price point,use a zipper made by one Italian company.The"new" zippers of the past 5 years or so ,are VERY reliable from a leaking point of view,whereas 10+ years ago ,not so reliable
3)Please be aware :when you use zippered waders,and you pee say 4 times in a 6 hour period,you will usually pee 2 times in the same time period,Just saying...it's been my experience and I have heard a few friends confirm this quirk of human nature🙂