I've always found that the wheel of excitement is most likely to give out a prize... the wheel of mediocrity I've only won 20 NP max.
I say Knowledge but these days I have been getting crap. Monotony is long but you can see what you are getting, that way you can decide if you want to keep it spinning.
I used to get awesome prizes from Knowledge *cough* Scroll of Freezing *cough*, but I haven't gotten ANYTHING good in a while. Excitement, I'd say. More good than bad.
The wheel of monotony is my favourite, mainly because the prizes are constant, you're more likely to win something than not. And if you use the guide, you can tell which prize you would win if you kept the wheel open!
i like excitement though keep getting 500 NPs. for monotony, i only get 20k -.- a bird -.- rock -.- or lottery -.- !
i find knowledge to be better as theres more chance to win something good like a job coupon and dont have to wait for hours
Ive always liked the wheel of excitement because ive actually won something good from that(the 10,000np prize).
i mostly do wheel of excitement because i'm too lazy to wait for the monotony... but i also love the wheel of slime!!! http://www.neopets.com/games/play.phtml?game_id=807 is free and you ALWAYS get something!!!