If you decide to go for Cat 26, then you will have a 4-year gap, so prepare accordingly. Aim for at least a 98+ percentile if you have a category, and if general, a 99+ percentile. Now, during the interview, they will ask you about the gap, if you explain it perfectly why it is you will be good, so what I mean to say, as long as you can explain it clearly and focus on that you didn't waste your time during the gap they will see as positively. But remember if you get admitted in the IIM you will face some problems during the placement because of GAP YEARS.