Are you using hierarchical stepping? How are you handling situations with no information? How are you detecting this?
I tried it out before, but had problems with getting it accurate enough. I didn't use a hierarchical approach though, which limited the search distance quite a bit.
I have no idea what method I'm using. I just tried making ssr from logically thinking it out
1) I calculate a view-space position from the current position at the depth buffer.
2) I loop through n amount of samples
3) I step along a ray (in view space), and at each step I convert back into screenspace and sample depth
4) I do a binary search to make sure depth information wasn't missed
5) Calculate some fading and output color
I don't have any fallbacks yet, and there's a huge problem with the range-check