I know this is a controversial topic with no ultimate right answer, because it differs from person to person, depending on several factors, the most obvious being, of course, how much time you spend practicing it. However, I'd be interested in what time you think one needs to perfect...
Here's my 'Take' on a sleight made famous by Sharps, Mechanics, & Cheats. Although 'not there' yet, It will take months of practice, years to perform, and a lifetime to perfect. Here's a 'taste' for now.
I was so glad that I made the video instantly :D
Gonna practise a lot more and make it much better. Been working on the center deal on and off for about a half year or so. Got a family and kids now, so don't have as much time when you don't work as a magician you know.
Anyways here it is: