Hey duffer,
I actually use aftermarket filters on my tractor as well. I don't have any concerns about doing so. My reasoning behind my warranty comment is that Mahindra keeps their filter specs secret, so there's no way to verify if a filter meets/exceeds Mahindra requirements for flow rate, filtration efficiency, bypass valve pressure etc. Yes, in a warranty situation strictly speaking Mahindra would have to prove that the use of an aftermarket filter caused an engine failure, but if they chose to deny for that reason, it would be difficult (although not impossible) to refute without detailed filter specs.
I wonder if it's possible to find out that information from the engine manufacturer. My 3016, for example, has a Mitsubishi engine. I'll have to look into that sometime.