I'm 65 years old, have been climbing with hooks since the early 70's and I'm very comfortable using them. But, I do want to caution you that they are not for everyone.
For anyone that has never used them, there is a leaning curve that deals as much with gaining confidence in the hooks as climbing technique. Even though they are my primary way to hang a treestand I still don't go out of my way to recommend them to hunters. They can be extremely dangerous even for an experienced climber.
Climbing practice, helps you to gain confidence that the gaffs will not cut out on you. I will say that every time you use them it gets easier and you become more confident.
When you first start climbing with them, I would suggest, just climb up a few feet then come back down. Also take short steps that track about 10" apart and don't hug the tree. All the climbing is done with your legs. You use your hands, not your entire arms, to maintain an upright position and in contact with the tree.
When hanging a stand you need to hang it below your climbing belt lanyard. Doing this you don't have to disconnect to step on to the stands platform.
Once again, they are not for everyone but they are certainly a light, quick, portable, way to hang a stand on most any size tree with or without limbs. Just beware of climbing cypress trees. If you don't set the gaffs good they will peel in a heart beat.