The Max would be a lighter frameset, but the compact geometry of the TCR was what attracted me to the design.
The ISP is also less compliant giving a harsher ride, but I prefer the short wheelbase of the TCR for handling.
The Giant with Di-2 might be a cheaper package then the equivalent max I suspect, they have always been good value for money.
One thing to be mindful of is the Giant OD2 1-1/4 steerer, which limits the choice of stems to a few manufacturers if you ever wanted to change the standard stem out, but it does make the front end stiffer.
The velolab report is a good read but it is biased.