Worked here for just about 5 years now in the field. This is a company that has a great product, but I feel as though my stomach is full of Kool Aide now and I have no room for anything else. If you are field based, don't expect a healthy work-life balance. It's probably the same game that's played across many organizations when managers don't know what goes on at the day-to-day customer interaction level. As a TM, be prepared to work - this is not the type of product you can unload onto a physician as there is a lot of clinical and technical interfacing that must happen. Because of this, there are constant scheduling issues with clinical support since everyone is stretched too thin and juggling too many things.
Because of the mass hiring that occurred in 09-10, there is little career potential for upward growth. They've been hiring people from outside the region and outside of JNJ for RBD and management roles. Many clinical and sales people have left because the core of what the job entails - helping the patient, has turned into helping JNJ's bottom line.
There is no clear pathway to jump across different departments or other interests internally - most have decided to jump ship altogether. If you are seriously considering Biosense as a field employee, you will be pulling 10-12 hour days pretty regularly.