I am planning to add a keel strip to my SKUK Explorer.

Is this a 'preventative' keel strip on a newer boat, or are you covering up some damage?

If the boat is still in 'new' condition, I'd wait and see where you actually get the most scratches before adding a keel strip. I seem to run up on rocks with barnacles and get scratches on the flatter sections of the hull.

I've put on KeelEzy, polyester keel strips, and done hull touch ups with epoxy.

Do you have supplies of any kind 'on hand'? This could affect the cost and your choices.

You can get good results with either polyester or epoxy, if you know what you are doing. (This is just a 'sacrificial' strip, not an actually glass repair with laminate damage, correct?)

Epoxy and polyester resins are quite different (beyond the smell, which is an issue depending on your work space location) in their working properties - if you have used only one of them in the past, stick with it.

It's easier (and cheaper) to build thickness with polyester gelcoat than epoxy.
Color matching is easier with gelcoat.
You can do 'spot repairs' with resin; KeelEzy would need a full replacement in most cases IMO.

KeelEzy is a good product, but it is on the 'soft' side and boats tend to hang up on rocks rather than sliding off. If most of your abrasion is from dragging the boat up sandy beaches, KeelEzy would be a good bet. I wouldn't try to use anything but a full-length strip of KeelEzy (despite the price) as exposed 'ends' are a spot where the strip will be liable to peel off. You need to be careful working around your skeg box (assuming your Explorer has one) to 'hide' the cut ends. There are YouTube videos on this.

Whatever you choose, get lots of masking tape and take your time getting a reasonably straight line.

Good luck!