i think swiss balls are great for core stability and have a huge role in the rehab and prevention of LBP. I feel they will be the focus of many exercise programs over the next few years. but i think you need to pick your patients. I tend to start my patients with a basic trans abd contraction in crook lying then progress to basic movements with trans abd contraction in lying and standing. Once they are good at this, i may go to the ball and start with simply sitting and then adding in UL and LL movement in sitting etc. As patient gets better can progress to more challenging stuff such as role forward with knees on ground, kneeling on ball, feet on ball and elbows on ground etc. the key is to maintain the lumbar spine in a neutral position using your stabilisers. If the patient flares up or cant do it regress the exercise as its prob a little too hard. The pilates courses etc are really good for examples of exercises you can do - they show basic ones and more challenging stuff also