There is a caveat (see below), but the short answer is yes. The answer "is it good for 5 bucks" is "YES!!! ABSOLUTELY!!!"
Now...as for the strange feature: those round thingumies on the thing. The "it takes some getting used to" is probably an understatement. I like it better than using a trackpad on a laptop, but that's about all positive I can say about it. In 3D games, I never found a sweet spot between "nauseatingly sensitive" and "turning as if standing in mud" with the right one, and when playing a 2D game (I mostly play platformers) I quickly found myself torn between the lack of touch feedback with the pad and having to use a joystick (which I settled for in the end).
I ended up buying a PS4 controller not long afterward, and hardly ever looked back. So if you've already got those (or xbox one, if that's what you fancy), then I'd leave it. But for this price? I've payed 4 times that amount on far less controllers.
Because make no mistake: in all other fronts, the thing is at least reasonable. Perhaps it's me, but whenever I tried a wireless connection on any controller it was always shaky or the range was short. The steam controller is just plug & play (or merely installing/configuring the drivers once). The buttons and the joystick are...erm...compared to PS4 I'd also go with the latter, but they're certainly decent for gaming. Compared to your standard controllers, you also have two extra 'draw' buttons at the back. These also work fairly decent; it's only because of lack of muscle memory (or that no game is configured for them - though you can configure all of them to use it if you want) that I rarely used it.
And perhaps a stab at other controllers including wiimotes: the batteries don't drain if you're not using it. In fact: I've never had to recharge them. Okay, I didn't use it hours and hours on end, but even so...I'm not kidding when I say the (standard AA) batteries last a long time.