lol, this is my kind of topic!
Right, lets get things started...Vee brakes are amazing! don't let anyone else tell you otherwise. If they say they are crap thats because they have never ridden with a nice setup or can't set them up for shit.
I have been riding for 13 years now and I have ridden a rear vee for 5 years. In that time I have Won world cup events, got into UCI world cup finals and come 2nd in the British champs. I am not trying to be big headed, but just letting you know I am not just a newb.
What you need to understand with vee is that they work in a different way to maguras and as such, do not feel like maguras. A lot of people swap from a maggie and and then say the vee doesn't work as well...so remember, they are different.
A vee won't have as much bite as a maggie (possibly why a lot of people diss them), but a vee has a LOT of sheer holding power, more than any maggie can give. This is where my love of vee brakes comes in..I mean why do you want so much bite in the first place? the ONKLY thing its bad for is backhopping down slopes, but I just turn the bike sideways to counter that. Holding power is the most important aspect of the brake in my eyes, just think of all the times your depending on the brake....taps, gaps, hooks basicly any move where the wheel is wanting to go backwards, this is where a vee just kicks ass!
Other points to remember is that a vee with good cable, is easier to pull than a water bled maggie because you can adjust the springs to be as powerful or slack as you like. The pads last longer because they can't wobble and wear at silly angles, vees are lighter, you can get spare parts nearly anywhere, no pipes to burst, cant freeze, are more adjustable and easier to set up.
I think thats everything