If you're referring to the Jim Beam decanter set from several years ago, they are much larger than G-scale and their wheels don't turn, so there's no way you could use them for an actual operating train.
We have one of those sets in a display case at our clubhouse. The set is close to 12 feet long with the engine and tender.
If they will run on a 45 mm track and aren't too big for the tunnels etc, why not?
Rgds Ian
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