I've used that Nashbar set before. Here are my impressions/opinions:

• Plastic tire levers are plastic tire levers, pretty much no matter from whom you buy them;
• I'll bet you already have some screw drivers;
• I'll bet you already have an adjustible wrench (although the wrench that comes with the kit is actually of fairly good quality);
• The pedal/crank bolt combo wrench is great;
• The crank puller works just fine, but the threads on the tool dulled a little bit on a crank in which I had to chase for the crank's threads. It still works fine on normal cranks, though. It is also both square taper and ISIS compatible;
• The generic lockring tool works fine, but it's not as nice (or easy to use) as the Park/Pedros ones;
• Allen wrenches are crap;
• Spanners are flimsy and almost useless;
• The BB tools they do give you don't work with all BBs (I realize that would take a lot of tools, though);
• The spoke wrench is fine, but I've rounded off a few nipples with it (granted, they were aluminum nipples); and
• No 15mm wrench?! You are expected to use the adjustible wrench to remove your wheels.

Bottom line is, you're going to spend possibly twice as much if you buy all of those tools individually from quality brands. Do you really need all of those tools? Also, I'd second whomever suggested before that you buy a quality set of metric allen wrenches. Make sure you get the kind with the ball-like thingies at one end that allow you to use the wrenches from an angle (it's really useful sometimes, but not necessarily on bike applications).