I just published a quick review of the Nikon E-Plan 4x objective over on the Photomacrography forum. I think this objective is an excellent alternative to the Nikon M5 recommended for the <$400 Setup recommended on the Coin Community Forum, and is available now on eBay for <$40 from multiple sellers. Check out my review:

https://www.photomacrography.net/for...285629#p285629