RE: Has anyone climbed trees using foot spikes?
First thing make sure you get tree trimmers spikes they have longer spikes than lineman spikes(does that make sense)this will make a difference especially when climbing trees with thick bark.
2.SAFETY BELT WHEN CLIMBING!!!!! This is a no brainer.
3.Be very careful when first starting to use them that you don't miss when climbing cause you will kick them right into your leg and it HURTS and will leave a nasty scar.(don't ask me how I know I just know)
4.Remember to stay on the front of the tree when climbing and keep your legs straight when not taking a step there is no feeling like having a spike come out while in the middle of a step cause gravity does indeed work.
5.If you get a pair always keep your spikes sharp and free of burrs that way you don't have to stomp them in you can just step up a tree.
6.Strap them on tight if you get a pair this will make sense,I like to have mine as tight as I can take so there is no wobble at the ankle or knee.
7.Lean back into your climbing belt to keep your weight on your feet if you don't you will learn the meaning of "burning a tree" again gravity works and if your spikes slip you will find this out.
8.It's harder than it looks so if you get a pair practice,practice,practice on tree in your front yard,start small and work up to bigger trees.
9.I always inspect mine before every trip into a tree even if I was just in 1 the day before.
10.Be wary of thick barked trees as if you don't get a good step you will only be in the bark and not the meat of the tree.
These are just some things I can think of off the top of my head I use spikes to put up and get into my tree stands I also have used them to make a living trimming trees.Above all BE VERY,VERY CAREFUL WHEN USING THEM.I am not trying to scare you just stating facts about the obvious dangers.I have burned a few trees,missed a few steps,had spikes kick out on me,stabbed myself in the leg with a missed step,face planted on a tree(this happens when both spikes kick out and you go face first into the trunk)this generally precedes "burning a tree".Burning a tree means you go down REALLY fast kinda like hooking your toes on a ladder and letting go and sliding down said ladder.It would be helpful if you knew a tree-trimmer and got some first hand instruction but if not like I said practice on small trees at first and work up to bigger trees.
I hope I've helped in some small way please be careful.