My thoughts on the whole "making a table play hard so when you shoot on a regular table it is easier" doesn't make sense. Tough pockets might make you better at pocketing balls but it will also take many shots away that you need to know. Tight tables can change the way you approach the game. If you will be competing on regular tables you need to know how much you can cheat the pockets and how cheating the pockets will affect your cue ball control. Its my belief that to be competitive you not only need to be good at pocketing balls but you need good cue ball control and position play, pockets that are too tight can affect that part of the game. I wouldn't consider anything bigger than 4 1/2" and I might go as tight as 4 1/4" but beyond that I believe you are changing your style of play too much. Besides, anyone halfway skilled should already be a good ball pocketer, its cue ball control and position play that really sets skill levels a part.