Do I dare go up a limit?

[jjakque]

I have been playing Sng at $1.20 buyins.
18/11/2.19, 600 tournaments played.
9 players ROI 28%
18 players ROI 27%
45 players ROI 31%

ITM 31% with 8% 1st, 8% 2nd & 6% 3rd.

I now have 100 buyins for the $5.50 Sngs.

Will I see a drastic change in the level of competition at this level?
Should I play the 9, 18, 27 or 45 player tables?