BJ is only -0.5% or something. So if you're betting $2 you expect to loose 1c.

If the bonus takes 1000 hands to clear $100, then you are making 10c per hand. Your expectation is now +9c per hand. I don't know the actual numbers, but it should be easy to figure out. It's extremely unlikely a bonus would be -eV.

The bigger concern is chance of going busto because of variance. I meant to do the calculations one day but got lazy. A $2 bet from a $100 roll has a pretty small chance I believe.