I got it after 3 years and about 50,000 hits but the hits were all over the place; sentiment scoring, writing, transcription, image tagging, audio recording, data entry. Not sure if variety is the key but it probably didn't hurt, either.
My Masters story....
2009 - end of year started mturk
2010 - awarded masters at beginning of year with less than 1,000 hits. It was awarded based on recommendation of a requester I was working with. Quit turking shortly after because I didn't trust Amazon with my bank info.
2013 - received an email saying come back and use it or lose it. Pfff, who needs that.
2017 - came back to mturk, having masters would be nice, but I don't even know if it's possible to get masters back again? I had money sitting in my account from 2010 that I never claimed and wasn't able to for some reason. Amazon absorbed it.
If it happens again yea, if not, oh well. Not having captchas would be great.