If you have fruit trees, you probably have acreage. If so while the manual edger will work great, the back will feel better with a string trimmer. You can get one for the price that is shown in the URL's you posted.

For about 50% more you can get one that will save your back and last a fairly long time

I have had the one in the 1st link for decades. Mine is so old that it just has a bar across the top. It works very well and I normally use it to make the slot for edging. Either one would work for you. Lee Valley is great.

Agree half-moon edgers are good things. I don't use mine as much since I put in the brick edging, but remember it with fondness.

Whether or not it is worth the money to get a fancy-pants ergonomic one, I have no opinion. Mine came from Agway.

I have one similar to the first one, except it has a long straight handle. It came from Lowes. It works well. I can make curves and circles with it.

I'm not convinced by the circular handle which you have to grip at the sides. A T handle works very well and you can get a good purchase leaning down on it while your foot does the heavy pushing. I've only ever seen Ts over here where the sharp cut edge is the norm for a lawn. The price seems high too. They're half that here even for the most expensive ones.

I use one and love it. I’m a small 70+ female.

This is mine. It’s a garden weasel. Cheap and hard to beat.

That's all I use, is the manual edger. I hate power equipment in the garden. Two exceptions - a Sawz All and an Electric mower. I tried to keep in mind keeping the edging a minor job in the garden when i was planning. And really, I neglect the edges when i can't get to them and then really enjoy it after i've finally caught up. [g]

And once you've got your sharp edge with your half moon, use a pair of edging shears to keep the grass in its place. You only need to use the edger occasionally. Maybe only once a year if you're lucky.

(Actually now that I think of it, I only use the edger to create or enlarge a garden as I always create a permanent edge using a cobblestone like border.)