Why are you concered that the fork doesent have lock out. It is only "safe" to lock out a fork and ride it is when doing some light riding, NOT when dirtjumping. If your not going to be doing any DJs or FRing then this is not the bike for you.
As for the components they are all pretty solid except for the derailleurs, you will probally have to replace them in a year or two. Or you could go single speed, witch is what I would do.
edit: Why is the saddle the first to go? my friend got one for $20, it's is a great DJ seat. Why do I get the impression that this bike is not for you??