We use Conquer Maths for DS & DD aged 8 and 10. It's certainly suited out children. The lessons are really clearly explained and you can answer loads of questions until you get the hang of each subject.
Conquer is fabulous, and you get a good discount with the home ed code (which I can't remember off the top of my head...). I think we paid £56 for a year's subscription. It also goes up to A level now as well.
The only snag with Conquer is that some people feel there's not enough practice on some topics, so they need to supplement with other resources. Ds uses Khan Academy as it's quite similar in the way it's presented, plus it's free.
I think you can do a trial with Conquer - worth checking out.
I have no experience of Education City though so can't compare.
I'm looking to sign my 10/11 year olds up to a maths programme and wondered how effective/enjoyable Conquer Maths / Education City really are? Education City is cheaper and has lots of subjects available, but is it as good as Conquer?