Having recently had some custom mods done, I can vouch for the fact that the authors of WP AMP are not only competent and obliging, they are also trustworthy and ethical. What a relief it has been to find to find a WordPress AMP package that works well, is easy to configure, and comes from authors who are fair and considerate. It has been a pleasure to deal with them.

Having first tried ampforwp, I was unhappy with it for multiple reasons. I was so glad to find this alternative that works well, is customisable, comes with regular upgrades and improvements, and is very well supported.