I know exactly how you feel. It's hard to justify spending $20, $40, or $100 for an important piece of gear that will most likely (if you're lucky) never get used. I feel like it's a waste of money to have a good quality tool sitting in a closet. However, like everyone else mentioned, when you need to use it, that's not the time to find out that your multi-tool isn't up to the job.

What I do now, is whenever I buy some new piece of gear, I relegate my old gear to the emergency bag. That way, I know that I can count of it when the times comes, plus as an added bonus, I get to buy new toys. In your case, if you don't have an immediate need for a multitool, just keep waiting for items to go on sales, you will eventually find something that suits your purpose. For example, I found new SOG Powerlock S60 multitools, normal price $90+, for only $20. I also bought a bunch of leatherman kicks when they went on sale for $9 at Walmart, so I've been able to keep one in every car without breaking the bank. New versions of tools come out every year, and when they do, the older (but still functional) styles are usually sold off at big discount. I regularly see used name brand multitools going for $20-$25 when people get tired of them. This pretty much applies to almost everything I buy, so keep your eye open, you will eventually find what you want.

Oh yeah, regarding the knock-offs. While name brand usually is a good indicator of quality, that's not to say all no name tools are crap. A lot of them are, though, and it takes some experience to be able to tell which ones are good.

Edit: I also forgot to mention that there are other options other than multi-tools. Unless you absolutely want a multi-tool, you can always carry a separate knife, pliers and screwdrivers. You can probably get decent quality tools that individually perform much better than most multi-tools for much less money. It's not as nice and compact, or as fun to play with, but it works.