Ospreys, Slammers, Eagles, Sidewinders, Stocker Trouts, Optimums, BassTrix, Charlies, Parmus, Generic Trouts, Mission Fish, Castaic Soft Trouts, AC Plugs......it never ends. I'd love to say that they all work and any of them would be a good choice, but that wouldn't be the truth. Big baits are just like any category of bass lures, each has it's own niche. It's not like any one of them would be the solution to every situation.
What I try to do when outfitting a guy who wants to target big bass is to find out where he is fishing and set up a game plan. Without a doubt, the Osprey is my number one choice for most conditions. It's a visual bait, so in clear water it's slow, shallow swim has great appeal to ambush minded bass. The Eagle, Optimum Suspend, Generic Swimbait, and Sidewinder are all like-minded soft plastic swimbaits, what I personally like about the Osprey over all of them is that there are several modifications I can make to the bait to expand it's potential. The color representation of the Osprey is also far beyond what any other company is pouring.
The Slammer is king of the wood baits, but that style of big bait is not as commonly used as the soft plastics here in So Cal. The wood bait excels when there is less water visibility(or at night), bass want a bait dead-sticked in one spot, or when warming water temperatures encourage bass to become more aggressive when feeding. I also think the Slammer can be a good antagonizing lure when bass have seen many slow, quiet swimbaits.
The first two big baits to own would be an Osprey and a Slammer, two different baits that will help cover most possible situations.