I use both programmes (Whizz and Mathletics) and both are excellent but they are very very different and you cant make true comparisons.
Mathletics is very cheap in comparison and offers a whole range of lessons within each of the curriculum topics. You can assign (if you cant then contact Mathletics) year levels or curriculum levels. There is less to do on the year levels.
On each lesson there is a ? where you can be taught how to do the subject, but before you start the lessons there is a quick test to do first to see how much you understand on the topic (these questions tend to come from the earlier age). When you complete all the lessons there is a test at the end to see how much you understood.
You can repeat the lessons as many times as you want, but points stop accumulating after three goes.
Mathletics isnt quite as good at explaining new concepts, so if you struggle with something and dont understand the lesson then you are a bit stuck.
Mathletics uses a lot of technical maths language from a very early age.
It is a fantastic programme for revision revision practice revision.
The Live Programmes are also really good for practicing basic facts and if your child likes these then encourage them.
There are also problem games, which from aparents point of view just like games and you want them back on the lessons, but they are very important for learning how to read questions from a different point of view.
The downsides are you pick an age or curriculum level but sometimes children do vary on the levels in the different strands. Mathletics can make adjustments but parents cant.
Overall it is a fantastic product for the price, and if used regularly for 12 months doesnt really cost much per week. To get the best out of it they recommend a minimum of 30 minutes but you will see improvements if you use it for 90 minutes a week. (times pinched from Whizz recommendations)
Questions are not gimmicky with fancy graphics and you can get through lessons very quickly.