Is it a buy one or the other question.
The 850T is probably a little more classic with the round fin engine.
You can fit decent inserts into the 35 mm forks.
If the chrome bore cylinders are not replaced already, factor in the best part of $1000 for the likes of Gilardoni piston/cylinder kits (Nikasil)
Depending on the year, it will have no oil filter (only a gauze) so if the chrome has lifted in might have gone through the engine.
It would be easy to overspend to get a good bike.
The Mille is a bit of plain jane parts special but has the square fin 948cc (small valve) engine so no cylinder problems, the extra 100 cc might add a small amount of torque. (but the seat of the pants will depend on the flywheel weight)
It would be a good tourer.
If I didn't have a Loop I would have gone G5 as a second choice.
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