If you want to play around with it, here's the craft file:
https://dl.dropboxusercontent.com/u/4152380/AsterBuster%20Fairdyne.craftMods you will need: Near Future Propulsion (engines and electrics), Procedural Fairings (little nosecones on the boosters).
Mods you will want: Mk2 Cockpit Internal View
Special takeoff procedure: Enable SAS, step on the brakes, make sure throttle is zero. Stage. Right-click VASIMR thruster, set variable thrust to maximum. Press 0 to deactivate all electric engines. Release brake, throttle up and take off.
SSTO Instructions: Very much a temperamental craft, SAS tends to fail in keeping attitude. Get to 15k as fast as possible, then go level. Target flight parameters before air-breathing cutoff - 24km altitude, 1100m/s velocity, attitude 45 degrees. Push apoapsis to around 90km, and cut engines. Switch off RAPIERs, activate the PITs and the VASIMR, then coast. Once above 45k altitude, go full throttle along prograde, unfold solar array, roll to face it towards the sun. Use capacitor banks to keep the batteries from emptying. When capacitors are exhausted, turn off PITs and burn all the way to apoapsis on the VASIMR. Keep prograde. At apoapsis, reactivate RAPIERs to burn off any remaining oxidizer, then deactivate them again. If everything went right, the VASIMR working at half power from the solar panel's output should be enough to finish the circularization maneuver.
Action groups:
1: Toggle air intakes
2: Toggle RAPIER engines
3: Toggle PIT boosters
4: Toggle VASIMR thruster
5: Fold/Unfold solar array
6: Discharge capacitor group 1
7: Discharge capacitor group 2
8: Discharge capacitor group 3
9: Start/Stop recharge of non-full capacitors
0: Deactivate all electric engines