These are also good tools:
At least you get a bag AND tools. Most either sell one or the other.
All depends on what you feel you need. Some guys (and gals) carry EVERYTHING. Some just the bare neccesities.
I'm kinda in between. I supplement the OEM kit with some quality 3rd party tools, but for the most part, I THINK the OEM kit is sufficient to fix most of what you'd be able to fix out on the trail with the exception of a flat.
So, knowing what's in the OEM kit, you can go buy all 3rd party bits & make your own. Probably can be done for less then the OEM kit, and you'd have some better tools. Do what's going to make you the most comfortable.
And really, if you want a detailed list of what's in the OEM kit, just PM me and I'll get it to ya.