Magura Julie as THE best hydro disc system on a budget. $229
If you have that much you should get Hayes Hydros. Much more powerful and reliable then the julies and will run you $199 for the entire set. Magura makes a good brake but if you want power and only have 200 bucks then the Hayes are the way to go. The only Maguras with a lot of power would be the Gustavs and those run about $250 a wheel.