I have tried Live with both Windows and Mac OSX at 300 BPM, with Live as a Master.
- With Windows -> Tempo was climbing sometimes to 320 and more BPMs
- With OSX -> Tempo was tight
I guess it is due to windows USB/MIDI drivers that bring more jitter.
Moreover, if you use bad quality hubs, it may be also linked.
By the way, you should try two BSP together if you can (Clock DIN 24 or MIDI DIN) before incriminate BSP.
Other manufacturers usually choose not to display the tempo as it moves a lot.
Unfortunately, I think this feature that is there to help people knowing their tempo on BSP may disappear in the future as too much guys complain about it without really hearing any sync issue.
Regards,
Y.