depends upon use, onroad vs offroad being one criteria.
if a Diesel is converted to Petrol, best to avoid Desi conversions unless its done with a petrol engine offered in same vehicle (e.g. 4D56 with 6G72) , other systems in addition to engine have also been changed and it is done at a place/city which is is known for conversions. For proper conversions, compatibility of other drive train parts has to be considered. Desi mechanics love throwing a Toyota Non-Compatible engine in Jeros which leads to various issues.