The faster pull speed is good but I heard it is not good for stringing poly because you want to pull it as slow as possible. Also many people have said the Star 5 overshoots the tension by as much as 8lbs before returning back to the set tension. Both are very accurate machines.
Stringing on the Baiardo is more ergonomically friendly as it tilts for the user but when you do the crosses and it tilts even more, the clamps slide downwards and gets in the way. It's definitely more eye candy but you really can't go wrong with either.
I know they use the Baiardo at the US Open and the Star 5 at the French Open. Which other major tournaments are these used exclusively at?