I recently bought Estlcam V11 and am very happy with it. I am using an Atmega2560 board, running the estlcam controller firmware as it allows for 8 inputs and 8 outputs to control a variety of peripherals. He has also developed a pendant for use with the system, hard to find on his web site, you need to translate the site using google chrome to find it. It is a nice addition to my OX, I will post a pic once mine is finished.
I had looked at it too. I found that he became greedy as he became successful. When he started it had cost $40 (US ) now that people like it he raised the price to $60 (US ).
Beyond the fact it's easily worth twice what he's asking, increasing the price as features are added or improved would hardly be considered greed.
The flexibility of the controller along with the ease of use and rich feature set make it worth every penny in my opinion.
And you can use it for free with little feature limitation. I am now trying it out, once I figure it all out - and if I like it - I will gladly pay the $60. I like that I can import an STL and mill it. I can buy small ABS and acrylic pieces (easily glued) for $1 per pound out of the scrap bin at Tap Plastics. I find it much faster to mill a small part from a Thingiverse STL than to 3D print it. It is also nearly 10x cheaper per pound as long as you optimize your cuts.
The only feature limitation I have seen on the trial version is a short time delay that he has built in.
While I have your attention, I noticed something weird when I set it up. On GRBL Panel I had my drivers (DQ542MA) set at 1/8 microstepping and that was used for calculating my steps/mm settings for GRBL panel. Everything was spot on after calibration. When I switched to Estlcam, I had to tell the software that I was using 1/16 even though my drivers were still physically set to 1/8 or it would only go half the distance I commanded it. It seems weird.