Any difference between the hiker and hiker pro?

A bandanna does work as you described, but a regular coffee filter will probably filter a little better than a bandanna. Just toss a few in with your filter along with a rubber band. The Hiker Pro also comes with several small adapters that enable the user to filter water directly into a hydration bladder via the drinking tube, IF you have it set up correctly and have the correct parts. After all that I have used my Hiker Pro I haven't explored this yet. Had better things to do I guess. Personally I like the quick release feature so much that I would probably pay the extra few bucks for it because it allows you to easily unclip the output tube and store it quickly, but when I bought my Hiker Pro I found it on sale for the same price as the Hiker.

The Hiker Pro has a quick release feature on the "in" water hose making it easier to attach & remove. A nice feature but costs an extra $15. They both have the same filtering properties.

The main difference is the hiker pro comes with an extra mesh screen that wraps around the filter, to extend the filter's life. The screen can be cleaned in the field, making the system a little more durable. FYI: If you're pumping from a scummy source you should use some extra pre-filtering no matter which filter you use (I usually rubber band a bandanna over the prefilter). It's easier than cleaning the mesh screen, or replacing the filter.