Its also not always about the "Best" it's about picking an item that people will buy. The 750 Evo is arguable better but it is more expensive, in reality most people cannot tell the difference. Only people preforming large I/O operations like SQL/MR Databases, Video Editing and 3D Rendering will never come close to the maximum IOP's of the drive.
If you're looking at purely Read/Write between EVO and PRO, there's about 20mb/s difference in Reading between EVO and Pro and about 100MB/s on writing. So for everyday computer use, you probably won't notice the difference between the EVO and the PRO since the majority of us aren't reading and writing files over 500mb. You'd only every really notice this when working with extremely large files.
Yeah. The other time it would matter is if it's going to be doing really really intense amounts of read/write for a long period of time (like say, a decade or two), but realistically the Pro is overkill for consumers.
Correct me if I'm wrong Surgical, but doesn't the Samsung Pro Series have better benchmark results than the Evo Series, and is better for the cost? :)
Edit: Yes they both have their Pros and Cons but The Pro series is said to be one of the fastest consumer SSDs :3.
From a consumer standpoint, you're basically not going to notice the difference between the Pro and the Evo. Unless you're constantly writing to it all day every day for the next decade, the Pro is not going to make a difference. Get the cheaper Evo for personal use, get the Pro when you're putting together a machine that will spend all day computing in a lab, or building a server for some customer with specific needs.