What size pot to go up at a time.

[gladwrap]

Hi Everybody, I am new to this forum,but have been growing orchids for a year or two,I have a lot of repotting to do with my aussie speciosums that I have had since babies(50mm pots) and as they get bigger I just go up a pot size,but was wondering, am I slowing slowing down the growth rate by doing this or should I go from say a 4inch pot to maybe an 8inch pot so as not to disturb them as much.Would appreciate some feedback on this thanks.