I installed a T-Max system in the week thats comming to a halt now.
I all honesty; I fitted the Aux battery in the back & off course the relay/solenoid in the engine bay. There is significant more work to installing the T-Max than the NatLuna. So if one if paying for labour, worth having in mind. The display is also abit bigger. If space is tight or cramped, think abt that too

The T-Max kit is indeed not as dear as the National Luna kit.
The NL also has a display on the relay/solenoid itself, so IF the (optional) remote display goes down, there is still the possebility to monitor the condition. Then again, the NL takes up abit more space, which I found out last week when I fitted it to a LC100.
I used, in both vehicles, a marine grade fuse box (BlueSea style) having both fused Positive & Earth negative terminals. So all cables come back to 1 point. Have not bothered with LED displayed "fuses"....
I do also have the National Lune (stand alone) battery box which holds both relay/solenoid & dispaly in one unit.
Its being fed thrugh an Anderson plug. Quite okay it there is occational use only or it my boat needs some extra juice.
Many ways lead forward & the choice is Yours.
Which one is better & holds up longer, that remains to be seen
