Jas,
Other than bevel issues, the only time I've had an edge not last a shave is when it was overhoned - which is extremely rare. This is why you will likely join those of us that have spent months learning how huge an issue a good bevel is. Every time I thought I 'got it'. I found I had more to learn. Is it possible you've overhoned? Yup - but a very low probability.
There's absolutely nothing lacking in the existing vids on setting a bevel, but sometimes a slight variation in explanation or technique can unlock the door. Maybe this will help, maybe not. Our own Mrsell has a blog entry on it that is as good as any I've seen. I particularly noted the use of backstrokes on the low grit stones - which I've been using lately to good effect.
Honing help for newer straight shavers - Blogs - razorandstone
Some blades also just defy normal treatment. Glen can tell you about a dreaded sheffield wedge that I slaved over for more than 7 hrs and couldn't get a bevel. Blades that have seen indelicate use of buffers can also give fits. I don't know if either of these conditions apply.
They won't be the last blades that give you fits. I do suspect you'll break through the obstacles and find them worthy shavers.