Slower than expected USB 3.0 speeds?

I recently purchased a My Book 3.0 for my Windows 7 PC’s (both desktop & Laptop). My laptop has 2 USB 3.0 ports (HP Envy 15) and I used the included PCI express adapter card to connect my drive on my desktop. I was copying over a 18GB file to this drive from my laptop and was unimpressed with the transfer speeds (averaged 30-65MB/sec). It felt like USB 2.0 speeds to me. The speeds were about the same on both desktop and laptop. I spoke to WD support (not much help there) and they recommended that I send the drive back for a new one. I’m starting to wonder if that will make a difference. Anyone experiencing the same speeds/issues?

USB 3.0 Is not yet Supported by Windows 7.

It should be supported when Service Pack 1 comes up.