I inspect them regularly and run a file across them per Buckinghams instructions if they are dull or chipped up. A lot depends on how much tree work I'm doing, if I'm getting lazy while on the ground and leaving them on between climbs, if there are rocks on the ground, etc, etc. Seems to me like when I'm climbing full time they need lightly touched up about once every couple weeks or maybe a month. Mine are about 10 years old with maybe about 3 years full time service and used one to four times a month the other 7 years. I weigh about 170lbs. Other then needing new pads and straps, they seem to be in good shape with plenty of spike left. Matter of fact I kinda wish I had pole gaffs because the tree gaffs make my legs wobble when I'm on the skinny part of a tree.
I seem to have more kick outs or have them get stuck more often if I haven't climbed as much or all of sudden I climb a different type of tree, otherwise they seem to work fine once I get back into the swing of things. I haven't climbed a Shagbark Hickory in a long time but I always remember those as being a real pain to hook up.
