Bottom Bracket issues
I'd consider going back to square taper a bit of a downgrade. And buying a crank to suit the bottom bracket is a little bit backwards in thinking. That crankset you linked to would be fine assuming you want to keep the BB. FSA has been pretty good in my experience, but I can't say that with certainty for your case because I've only dealt with their more expensive stuff.

The thing you'll have to watch out for is getting the right chainline. If you have the wrong length spindle, you'll end up shimming something, which I never recommend unless absolutely necessary, or just buying a new one anyways. Without more information I couldn't make an assessment of the right length spindle for your bike. I didn't have any luck on FSA's website in finding their suggested spindle length to produce the standard 43.5 mm chainline, or whatever is appropriate for your case.

I would go order the correct BB if I was you, as long as you're willing to keep your crank for a little while longer. A new crank AND BB might be in order if you can afford it and want a smooth new setup. I don't know what you're doing though if those FSA BBs are only lasting 3000 km, though. I've had that exact same one, and it lasted so long I sold the bike before it wore out.