With this usb hub i would get around 2,6 tb/h. Since i'm new to this, is this a good bandwith? And how much would be the roi?
Here's very rough calculation,
Total initial cost: $3650
Gekkoscience Smarthub - 11 Ports With 9 Compac F and 9 fans 2.6 TH/s - $1800.
ALLPOWERS S2000 - 1700€ or about $1850.
Using https://buybitcoinworldwide.com/mining/calculator/ which consider rising difficulty, it state you can obtain $247/year. But it doesn't consider halving on next month, so you probably can obtain $123.5/year. At this point, i believe it's safe to assume ROI will never happen. And if you're willing to spend $3.6K in first place, you might as well as buy regular-sized ASIC (e.g. S21).