how long do you think this bike will last? form work and back? 20 miles a day? and i don't go off road.

i used to have a 1999 mongoose GT for off road.... but someone walked in and took it. i brought this bike to ride faster with the gears or whatever and to chase the ******* that took my mongoose. that is why i wanna know if i can upgrade.... to ride faster on road and maybe off but i needed a bike to get around too.

i was going to ask how to fix the brakes on my mongoose a few weeks ago ..... but someone had to take it and run... left hes crap for a bike. :/