I find the zip quite useful. Sometimes if I want a bit of relief from sore feet undoing the zip for the socks to breathe a little can help while I rest. If I remove the feet from the boots, I need to undo the laces and retie them with the zip done up. But when I get back t the hut / car absolutely beggared, I can slip out of them quickly and put on something else. (I dont like driving while wearing hunting boots- lack of feel on pedals)
For emergencies, I would still cut the laces. Undoing the zip is not a magic boot off technique.
Dont get much water through them, but they are not as waterproof as non zipped boots.
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