I'm sure you'll be fine with most any v-brake from a reputable company. Even the generic Shimano and Tektros have more than enough stopping power. Those XTs you posted will be really nice. If you want the most possible out of your brakes, I used to have some Shimano XTR v-brakes that were awesome. I think they were the M950 model. The way they're made, they keep the pad pressing completely flat against the rim with equal pressure from top to bottom, and the pads also wear evenly. As I'm sure you know, most v-brakes push more at the top due to their design and also have uneven pad wear. I think due to the design, they provided great modulation(better than any other v-brakes I've used) and were plenty powerful enough. I'm sure you could find them on ebay or something.