In every big pharma's life, a little Vioxx will fall. Yes, Merck (NYSE:MRK) is still feeling the sting of the cardiovascular side effects of its once popular arthritis-relieving drug, but that's the price you sometimes have to pay in the pursuit of blockbuster drugs.

You don't get to be as big as Inside Value pick Pfizer (NYSE:PFE) or Income Investor picks such as Eli Lilly (NYSE:LLY) and Johnson & Johnson (NYSE:JNJ) without a little rain falling from time to time.

However, what is Merck worth these days? More importantly, is it really worth more or less than the market thinks? That is this week's question, as Brian Lawler and Ryan Fuhrmann can't see eye to eye when it comes to Merck.

Duel on!

Merck was also an Income Investor recommendation, until this past summer.

Longtime Fool contributor Rick Munarriz does not own shares of any companies mentioned here. The Fool has a disclosure policy.