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http://straightrazorpalace.com/honing/16043-hone-lapping-101-a.html

I like the larger D8XX or D8C for lapping. If you just need to lap the C12k, a granite or marble tile (~$5) from Lowe's or Home Depot and some wet/dry paper is good.

The D8XX or D8C make sense if...

You posted this as I was editing my last post. Don't lap with the E. Use the D8C or coarser for that. Slurry has been known to strip the nickel on the E (or finer) hones.

For minor repairs and bevel setting, the diamond E 1200 is good.

The smaller surface area has pros and cons. If I was going to only own and sharpen 3 to 8 razors, the W4's will do it just fine. If...

Here's a review I did on the W4EE. It has both advantages and disadvantages vs the D8EE. Either way, you'll need to break the hone in first. The D8EE might be a bit easier to learn on for a new razor...