I don't know if they still make it but the Katadyn Guide model moves more water per stroke than the Hiker Pro, like 3-4x as much. It's not much bigger/heavier than the Hiker Pro, and I still can get the replacement filters. I find carrying a pump lighter than carrying extra water.

I'm just not a gravity filter fan, but it's nice to hear they're addressing the back flushing issue. In camp I'll fill a collapsing bucket with water and pump from that as needed. Works for me.