I've been using that same sharpener on that knife since right after I got the knife, 10 years or a bit more.
Go find a photo of a brand new Endura. As you will see, the overall blade shapes are nearly identical. Yes, my Endura has lost a little on the belly, but again, compare it to a new one. It's barely noticeable.
I would not say this particular sharpener "eats up steel."
I pulled the following from one guy's reviews of all types of sharpeners. It's pretty interesting.
http://sharpeningmadeeasy.com/knives1b.htm
"SLOT GADGETS
There is one class act in every category, and the Meyerco Sharpen-It is it for slot gadgets.* Designed by Blackie Collins to be so simple that it could be used on horseback, the Sharpen-It features tungsten carbide wheels for the first stage and fine ceramic wheels for the second.* The ceramic is so hard and fine-grained that it is more like using a steel.* With this combination, the Sharpen-It performs well at both sharpening and honing.
Unlike other slot devices, the Sharpen-It adds a third wheel to each set, giving two slots, and shapes them so that they sharpen one side of the blade at a time.* This setup allows you to vary the bevel angle somewhat.* Drawing the knife through at an angle decreases the bevel angle and gives a more razor-like edge. Since it is assembled with tamper-proof screws, I could not measure the bevel angles, but this information is less important because you won't have to use it with another sharpener to get complete results.
Also unlike others, the Sharpen-It can be used equally well left-handed.* It is so compact when closed that it can be carried in the watch pocket of your jeans.* The unit well built and sturdy, and features a tapered hone for serrated blades.* A less expensive model is available without the tapered hone."
So guys, would I use this sharpener on a "gentleman's knife?" Probably not, but then again, I don't own one of those. : )
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