Ohh... I already told you can have any one, it's your call now. Both are enough powerful for Indian conditions. In case of 90 HP, the real difference is noticed after 120. It's so responsive at high speeds but one seldom gets those speeds. I don't exactly remember but 100-140 kmph is a whopping 4 secs quicker than 75 hp (i think it's car-wale's review where i read it). Below 100, one may not feel any difference at all. In addition, i must congratulate you that you are learning quick buddy. Try to earn some 10000-15000 kms under your belt like that. That petrol/diesel concept is too difficult for a learner who is yet in the driving school. That's what i mean when i told you to "learn deep driving secrets" instead of out & out fast.You are learning it with passion.By the way, even if fuel prices for diesel & petrol were same, i would have still opted for diesel just for that torque & turbo spool. That's addictive in MJD's but it's confusing when people argument for diesel based on fuel costs only. Don't be confused, if you want a diesel, book it now. I don't want you to crib later & to opt for petrol because of excise. +1 to you & Keep your experience coming through.