Your ideas by our hands
I recently installed their Advanced Core Plugin and also had the privilege of communication with Support on a minor issue.
All I can say is - WOW! Prior to downloading the Plugin, I had some questions, and Support was very quick to respond. After I installed it I had another question, and again very quick respons. So, Support is quick to reply, thorough in their reply, and friendly (you don't feel like you're a bother to them, like some Devs make you feel).
Plugin works and boy - does it work. I left a review on the Plugin page.
I look forward to future dealings with Web80, both using their Plugins as well as dealings with the company - people are very nice to work with, and each of their Plugins offers something unique - many of which every site ADMIN could use. I just hope they start charging for these because they're valuable Plugins (I at least offered some snack/coffee money as a thank you - I just couldn't use such an excellent Plugin for free - and you should consider doing the same to support such a great Dev :)