I worked for a very well known company that's been mentioned in this thread and they make a wide variety of probiotic products. One thing to keep in mind is making sure that all of the strains in whatever product you choose are human strains intended to populate your intestines. Many companies throw in other bacteria strains, oral strains for instance, to beef up the CFU. For each problem a person is facing, specific strains in higher concentration often help. For instance, certain lacto or bifido strains will target digestion, IBS symptoms, or your immune system more than other strains. There are also strains like saccharomyces boulardii that can be taken after a strong course of anti-biotics, or in my opinion, while you're actually on them. So finding the right strain will really better serve you and your wallet. Customers often get confused and think something like 200 billion CFU is going to be better than say 30 billion. That's not necessarily the case. Also keep in mind many brands are shelf stable and DO NOT need to be kept in cold storage. I actually saw the studies Renew Life did with their entire line after exposing them to heat and they were still potent and actually slightly over the label claims in terms of potency. This was done over a several day period in Phoenix, AZ during peak summer heat. They left the bottles out in the sun and then tested them for activity.
Anyone eating tons of food, stressing out their bodies with high intensity weight training, and taking supplements NEEDS to be on some kind of probiotic. Digestion and immune system health are key for anyone. If you can afford protein powder, you better damn sure be buying a pro-biotic.