Very tough choice, so tough i have both and would struggle to choose. Love the mtg2 tint of the previous version, modded to around 7300 OTF lm, UI is again the earlier version and resets to low on pressing and holding the power(to step up modes). Newer versions carry on from mode your on.
Although the parasitic drain is not too bad on my version it is best practice to remove the cells if not in use for a few weeks+. Also the mm15 can not be locked out , the handle is useless imo so stays in the box. Ano is nice but shows up finger marks easy or any grease spots. I find the cells a little awkward to fit and have placed a plastic sleeve over the centre post as it was starting to show slight sign of wear from installing the cells(bit of a poor design as the cells can catch on the threads when inserting and can damage their wraps).
My tn36 is also modded to around 8400lm but with MKR's . UI wise i prefer it slightly as unlike the mm15vn, i can press/hold to advance without resetting to low,like the press/hold from off for moonlight which is handy in the middle of the night. Also can be locked out by a simple 1/8th turn of the body and cells are easy to install due to the carrier. Feels a hefty solid light and decent ano which does not chip easy.
So not exact models as you are looking at, the tn36vn does punch light out a good way with the MKR's for a flooder. Even though i find more niggles with the mm15 due to design(UI is better on newer versions now), i would still struggle to pick an out right one.:thumbsup:
So get both, let him pick and you have the other one :laughing: ,call it a win win situation