Purely for research purposes of course, given that ROK Comics, which I edit, has a comic creator too, I had a go at using the BBC's Doctor Who Comic Maker. Have to say I wasn't 100 per cent impressed: the flash-based online application doesn't load properly on my computer in two different browsers and the actual creation interface is fiddly and isn't exactly intuitive to use. (We've learnt some lessons from our own version which will be implemented in an update coming soon, but personally, I think it's much better than this).
The service is moderated, so there's no instant gratification when you create a comic, either - which I'm sure will frustrate younger users who wouldn't dream of having the Doctor using naughty words or asking a Dalek to do entertaining things with his suckers. Based on my own experience on ROK Comics, I appreciate the sheer volume of users slows this necessary aspect down, but still, my one page effort has taken three working days to approve. I've screen grabbed and assembled it below as despite the format of the comic, it seems you can't actually print it out, which is a bit of a blow, too. Click on the image to view a more legible version.
Verdict: The Doctor Who Comic Maker needs work (as does the script for this comic, but too late now). Older Doctor Who fans will of course instantly note the final frame reference.