Is USB 2.0 good for my 3 hard-discs ?

I use 3 Hard drives (HDD) for my Data storage they are connected through, USB 2.0, eSATA and SATA II also i have a New Mobo that has SATA II, III ports, my issue is am wondering whether the USB 2.0 IS good for my 3 hard-disks or should I change it and use the Mobo although I am contented with speed they have. I also considered using a PCI SATA 11 card but I think it has got some compatibility issues
