Okay, I am definitely not an expert, very much a newbie to mountain biking (been a roadie for years), but when I researched mechanical disc brakes vs. v-brakes, I found some sources that said that v-brakes are perfectly adequate if you don't plan on riding under muddy/wet conditions most of the time. Another plus for v-brakes is that they are lighter weight and less complex than discs.
I'm pretty much a fair-weather rider so I bought a used Titus Racer-X with v-brakes and find that they provide fine braking power. It may or may not make a difference that I am a lighter rider.
I also read that the disk brakes on lower-end mountain bikes are just not that good. V-brakes might be a better choice in a lower-end bike for that reason. If you go higher-end, then the disk brakes obviously get a lot better.
Just another data point .... like I said, I am new to the mountain biking world; this is just some info I gleened from my research. So far my v-brakes (Avid) have been fine for me.
Emily
Emily
2011 Jamis Dakar XC "Toto" - Selle Italia Ldy Gel Flow
2007 Trek Pilot 5.0 WSD "Gloria" - Selle Italia Diva Gel Flow
2004 Bike Friday Petite Pocket Crusoe - Selle Italia Diva Gel Flow