Switching company within the same industry, how to justify this?

So here are the pieces:

1. currently overqualified for my current position but underqualified to move up
2. the company i am currently working with is being outdone by another company i am looking into (largely due to outdated policies)
3. i want to move from my current company to the other company without shooting myself in the foot down the line (i would like to move back to my current company if i end up getting qualified for the positions down the line and i want to explain to my future employer why i want to switch without sounding like im down talking my current company)

also, is this just a generally good idea?

usa jobs
usa jobs resume
usa hotel jobs
usajobs
usa jobs federal government
usa job in ksa
usa jobs
usa jobs login
usa jobs gov
usajobs.gov
www.usajobs.gov
usajobs.com
usajobs
usajobs.gov official