Hi,
I've pretty much finished my first engine from a casting kit. I have a Stuart 10V waiting since Xmas 2016. I was a bit hesitant to tackle the Stuart kit due to the financial investment and inexperience. I was lucky enough to pick up a PM Research 2A Oscillating engine off ebay for $40 Australian. After making it I'm still a bit hesitant to start the Stuart.
I made a few errors and poor machining choices but it runs (on air) and it was a good learning experience.
Ben.