Before doing this, I'd only ever played the Amiga version, so I had no nostalga towards any of these versions. I picked this as it's a decent game that was released on all three platforms.
Graphics: 3/10 - In what can only be described as a Jackson Pollock or a voyage to colour clash central, this isn't the type of game a Spectrum can do. It's a mess, and hard to see what's going on. The picture above is the best this game ever looks. The control panel is easy to read though.
Sound: 1/10 - Almost none. A click when you shoot (which my joystick's microswitch does anyway), and a buzz or a ping here and there.
Gameplay: 5/10 - Not bad, all things considered. You get a fraction more warning than the CPC version, but other times you are right near to the top of the screen and things will just appear and kill you (the main screen is only 223 x 128 pixels). The controls are a little unresponsive and the game is slow and jerky. The beam weapon is better than the CPC version.
Graphics: 8/10 - Very nice. Easy to see what's going on. A bad point is that sometimes you see a blue square round the bullets if you shoot where the background isn't blue. The bullets, lasers etc all look nice though and move smoothly (there are 32 angles for the "holding down fire" continous beam weapon, the Spectrum only had 16). Most of the enemies are grey-scale, which is a dissapointment.
Sound: 5/10 - Nothing special. Some average music on the title screen, and shooting and explosion noises in the game.
Gameplay: 8/10 - Nice to control, but as with all the versions there are lots of "leap of faith" moments. You get more warning of things coming from the sides of the screen than the other versions (304 x 160 main play area), and the smoothness of the scrolling, shooting, jumping etc. make for a much more plesant experience.
Graphics: 5/10 - As seems to be usual for CPC games, there are some strange choices of colour, which make it a bit garish. The bullet looks the best of the three versions, and the enemies are more colourful, but overall not as good as the C64 (especially as the scrolling is jerky). The Control panel is difficult to read, and it also has a small screen (like the Spectrum version).
Sound: 4/10 - I don't like the title screen music, but the main game effects are okay (although it's all a bit of a white-noise fest).
Gameplay: 6.5/10 - The small screen area makes it hard to gauge jumps and the fact that the beam weapon doesn't reach to the edge of the screen (like the other versions), make it hard to kill enemies.
Graphics: C64, CPC, Spectrum
Sound: C64, CPC, Spectrum
Gameplay: C64, CPC, Spectrum