Hi emmt,
Some more questions you should consider.
How long have you worked for the commercial semistate organisation? What are your terms and conditions (over the last few years many css's have hired employees on contract)? Are you a memeber of the css's superannuation scheme (remember there are some benefits accruing to membership of these defined benefit schemes which are unlikely to be availiable on the "outside"). How secure is the business in the medium to long term. How secure is your department, location or facility? If you have a partner are they also in the public service, semistate sector or civil service?
ajapale