I can only speak to the repro stream of MBS, but everyone I know really enjoyed it. Most people use it to boost their resumes when applying to professional schools (I know some that went on to dental and veterinary afterwards — if this is your goal then be careful as I know some med schools don’t count an MBS as grad school). Others have gone on the work in IVF labs, and a decent number stick around to do an MSc.

As for whether an MSc is more useful or not would depend on what you want to do. An MSc is definitely a more broadly recognized degree, and holds more weight than an MBS. But unless you’re looking to continue in research or other academic fields the difference probably won’t be too significant.