Which solution would you recommend?
How much data? How often? What range? Is loss of any data acceptable?
You could use an XBee (coordinator) at the PC, and XBee (router/end device) at each Arduino to send data to the coordinator. Depending on the antenna style and power level, you can get various ranges. The XBees manage the collision detection and retransmission, assuring no data loss.
Oh, yeah totally right. I should post more details.....
Sending about 50 characters/Arduino/second.
Length, well.... max. 10 m with one usbhub there seems to be no problem with the maxlength of a usbcable (5m)
Data loss .... hmmm.... I'm logging over hours may be over days. So missing one package of data isn't so important.