It shouldn't be surprising that the device works instantly. There's no indicator light to show that it's working: you just plug it in and voila. The included memory card reader is a nice plus.
The small design of the Media Hub makes it so that it doesn't stand out too much on your system. However, $20 for two additional USB ports does seem a bit pricey. This is certainly a limited appeal product, one you wouldn't be rushing out to buy. If you do decide to pick one up, at least you can be confident knowing it will work exactly as you think it will.