Speaker stands height for Harbeth Compact 7es3

If the 18" stands get the tweeters to ear level then they should work fine. I think Sound Anchor makes three 17, 19, & 20" that fit the 7s.

Any opinions, Skylan vs Sound Anchor?

Sound Anchor. Bob makes some incredible stands.

Yes, for quite a bit more money...
the 20" skylans are not too high, unless you're short or lay down while you listen, even then they'd be fine. If you go lower the soundstage seems to drop in height. I'm 6', my chair is a normal 18" seat, and the skylans work great with my 7's.
As for comparing them to the sound of metal or wood, you can read plenty of posts on the merits or demerits of each.

Thanks, I've been advised to go with 19" Sound Anchors. I'm using 24" temporary stands, that sound pretty good, but I have not compared them.I'm 5'7", and the sofa is low.