I didn´t think that using a real TS (Ibanez TS7, in my case) made much difference comparing to the Line6 simulation on Gearbox. Sure it was a bit different when comparing them side by side, but in the end I didn´t even think it sounded better or worst, they pretty much did the same job.
As I love tracking things totally unprocessed to mess at will later with VSTs (or reamp in the future), I decided to sell my TS7. Maybe I will keep it if I find a nice reamp box around here, but anyway, IMO it doesn´t justify the trouble of putting a TS before the Gearbox and printing its settings on the DI channel.