Prepared for the Boards? Well, I guess my personal experience with an RN-BSN online program I completed does not apply to your inquiry. I was already an RN [ADN] when starting the online program, therefore upon completing my BSN I was not required to take the NCLEX, again.
I will say the online programs has many pros with just a few cons, IMHO. Cons; For the most part, the only interaction with other students & professors is via online message boards & emails. So, getting assistance can be challenge. Pros; Very convenient regards to when & where you study, which in itself brings many advantages.
I hope someone will reply that can share with you if they were prepared for the NCLEX after an online BSN/MSN program.