Adding a MARS mod to a nice radio is really stupid unless you are actually a MARS member. When I see a rig advertised with "MARS mod" it is an instant deal breaker for me, no telling what other ignorant things were done to it.
Oh piffle and nonsense. That USED to be true for things like butchered FT-101Es and Tempo Ones. But with modern radios it's just generally just clipping a diode or two that allows the transmitter to work on frequencies it's been artificially restricted from until "modified." I mean, feel free of course, whatever your criteria are - more used radios for me. I have an FT-817nd that was modified. It's perfect in every way, no harm at all done to it.
There is no calling me out on anything. The reality is the only reason I opened up the transmit range was to program the 60 meter channels. I was not willing to purchase a new radio with the 60 meter channels programmed in it to satisfy a passing curiosity of 60 meters. Make do with what you have on hand.
In the end it's the responsibility of the operator to use the radios on the frequencies that the operator has permission to transmit. If I as an operator has permission to transmit on frequencies outside the ham bands for certain cases (emergency service, MARS (or similar), marine communication etc.) then as long as the equipment isn't causing undue interference nobody would be wise about what I'm using. Or I can use a commercial station on ham frequencies and nobody would care.
If that shall truly be the case,,, so be it. However, do you in all actuality have the experience, skill and the properly calibrated and accepted laboratory test equipment to properly measure and guarantee that your clip of the diode open up the mars mod is in fact within the accepted emmisions standards that are in place for the service you intend to intrude upon with your non type accepted device? Obviously, being a licensed amateur radio operator does prove that you posess the technical knowledge to insure your aptitude in every fine detail including the emission standards of other services? So uh yeah, I suppose if ya dotted all those "i's" and crossed all those "t's" then of course , so be it! But, would it truly be prudent and confident to publicly condone such behaviour like using your rig for as example maritime use? How many really would or could extensively test their gear to such degree? I know many that could and I know an even greater that sadly cant.... Yeah I can remove a diode and I can even add a smd diode to make my radio behave different ways. But I am not going on the record to condone, recommend or admit the useful or practical application of use in other services, regardless if goes by unnoticed regardless if my emissions pass or not.... We must represent and set the example of proper conduct above and beyond. It is because we strive for and practice to the betterment of all principles of the radio arts, that we are allowed to operate use and possess such gear in the first place. Surely, nobody is indeed the wiser what service you operate what on.... but how many can honestly put their money where their mouth is when they operate their appliance radio out of band? All my radios are fully freq. capable. I also have held MARS credential for whatever thats worth. I wont say with 100% conviction my emissions out of band are in every other way compliant without such extensive testing. Compliant or not, yes it probably could or would go unnoticed but cant say its right for dead right perfectly compliant without such rigorous testing as is put forth when gear is type accepted.
I would not worry about it if I could be sure that the so-called "MARS Mod" was the only thing done, and that it was done right. But sometimes people who are inclined to do "MARS Mod" without a good reason, are also in to fiddling with the service and "hidden" menus and doing other "mods" of uncertain parentage that they find on the internet. They keep going until they screw something up, then list it on eBay as "Turns on but I don't have any way to test it".