I've had a Power Pruner (now Echo, I believe) since '92.
Works great. 13 ft. high is about as high as I can reach with it because it is too heavy to hold it with arms extended up high, but I easily get limbs 10 ft. high. Safety: have to watch out for where the limbs are going to fall to.
I like to use it for cutting firewood, also. Great for stuff less than 8". Can cut the wood standing up. Also use it for limbing trees after they have been felled. Can reach limbs without having to fight my way over to them. Very safe, because the chain saw is 7 ft. away.
I have an arborist's saw (Shindawa) that I also like. Light weight, handy, not very dangerous because it is easy to control. But it is basically just a small, light weight chain saw. If I have to climb a tree, that's the thing to use.
My largest saw, an old Homelite Super XL is a little faster, but the pruner and arborist's saws leave me less tired at the end of the day.