I wouldn't usually agree with cat-knapping usually, but in cases such as this I agree it is a necessary, and even heroic, thing to do.
Sometimes it takes a strong person, such as yourself, to do what might not be entirely legal, but is in the end moral and ethical. I believe what you did was a great thing, and I applaud the risk you took to do it. Not to mention the dedication, love, time and effort as well.
Good job. He deserved better than he was getting from the original owners. That's how I felt when Manny came to my house as a stray. I checked with my immediate neighbors but went no further. I felt anyone that let a 2 month old kitty out deserved to lose him. I also felt he was mine after I took him to the vet on day one as that cost a pretty penny lol. I don't think he belonged to anyone anyway as he was very dirty and had gingivitis etc.. Now he is very happy and healthy and his big teeth came in nice and white and shiny.
I'm just happy he is safe and happy in his new home, that is all that matters to me. he deserves the best, I wish I could have kept him, but my other kitties didn't accept him and they tried to fight him all the time. But he is the sweetest kitten ever, so loving!! I can't visit him because he lives three hours away, but I know he is doing great