Good range of responses. As a former professional mechanic I have an extensive collection of SAE, Metric and BA/BS tools, mostly Snap-on with some Mac, some Proto, some Craftsmen and some few others.

I learned early on that poor quality tools are a PITA and just failing is the least of the problems. When you round a nut or bolt, etc., it can create a far bigger problem for you.

I am definitely not in the get it when you need it camp with the exception of oddball tools you only end up needing once in a blue moon. It sucks when you need to fix something RIGHT NOW and don't have the tool needed. Yes, sometimes, perhaps most times, you can manage, but the right tool almost always makes the job easier and lessens the chance of damage to what you are working on or to your person, or other problems.

For my travel/grab and go kit I have mostly Craftsman, SK, Stanly and Channel Lock tools and they work just fine. Some were acquired when there were sales on sets of particular tools (screwdrivers, wrenches, etc), many were bought at various estate sales. I carry them in either a canvas tool bag (modest kit) or a Craftsman 2-drawer portable toolbox (much more extensive).

Sales are your friend, never pay full retail. But, my biggest bargains have been found at estate sales. Get there early and grab the best for usually very cheap. I stopped looking for tools at most yard sales since I rarely found anything worthwhile, but estate sales have been gold over the years, especially non-professional ones.