ZFS raid write performance?

[Quartz]

>>> a single hard drive won't do much beyond 100MB/s (maybe
>>> 120MB/s max) for sequential 128kB blocks, so that "landing pad" would
>>> probably not very helpful assuming you can saturate your GigE network
>>
>> Wait, I'm confused. A single GigE has a theoretical max of like
>> 100mb/sec. That would imply the drive is probably about the same speed?
>
> You won't get the theoretical max what with the overhead of Ethernet
> packets, TCP/IP overhead, and SMB protocol overhead.

Right, I know that, that's why I don't understand what Xin Li was trying 
to say.

I guess a better way to word the question is: would a raidzX using 
generic drives, samba, and 500mb-4gb files be notably slower at writing 
than ~70mb/sec. I have a feeling not, but I wanted to double check.