I love my BSR but am not using it much lately. Somehow it intimidates me a little and when I use it I try to forget is there. The main thing to remember when using it is that you need to reduce the lenght of the stitches to around 1.5.
When you first start doing FMQ, your stitches are very uneven and the BSR helps correct that, because if you move the fabric fast the needle goes up and down fast, and if you slow down so do the needle. If at this point you find that you stitches are even without the BSR, the only thing I can say is that you have conquered FMQ and probably don't really need the BSR. It is always good to have it, because if you don't do it for a while and want to get back to it, it will help you get even stitches again until you retrain yourself.
Maria