ROI is more important.

I don't use Poker Tracker. Does ITM categorize by the Buy-in? If not, I think that percentage is meaningless. I could have 99 losses in A 5+1 MTT and a final table in a 600+40. My ITM would be 1% but but my ROI would be pretty good.

Conversely, I could make the money 99 time in a 5+1 (basically return of buy-in) and one loss in a 600+40. ITM is 99% but ROI sucks.

These are extremes examples but you get the idea.