Well, the T7 takes twice (plus a bit) the cargo than the T6, so you will be making twice the credits.
It has kind of a space truck feel, it actually turns like a road truck as the yaw is far better than roll/pitch.
Its drawbacks are its lack of speed, poor armor and useless weapons.
Its an expensive ship in which you will have to be on constant lookout to avoid fighting.
Better be prepared in case you are interdicted... Invest in thrusters to up the speed, shields to take the heat while waiting for FSD to recharge, chaff and electronic countermeasures do reduce taken damage. But it is better to use some prevention, mind the scanner and if you see shady ships trying to get on your tail, bug out. Its a lot of ship and cargo to risk losing.
Oh and like was already said, the T7 won't land on outposts.