[Serica 5303] strap questions

I recently bought the Serica 5303 - I like it, a lot. now here are my questions for anyone who has one.

1. the mesh strap is nice, but I wonder since it is not a bracelet style but instead opens up completely when removing, has anyone experienced unclasping in normal use? I worry it will and will fall off without my awareness
2. has anyone removed the strap? I tried found it very difficult even with the 6825 tool, I take it that it is not something one can interchange straps with?
3. sometimes the clasp is incredibly difficult to open, as in I cannot open it with my fingers and need a tool such a Swiss Army knife to pry it open. Has anyone else experienced that?