[Mimedefang] Spam block?

[netguy]

Hi

Am getting *lots* of what looks like spam from the following.

arin.net reports:
WholesaleBandwidth, Inc. WHOLE-2 (NET-69-6-0-0-1)
                                  69.6.0.0 - 69.6.79.255
OptinRealBig.com ORB-BLK-69-6-10-0 (NET-69-6-10-0-1)
                                  69.6.10.0 - 69.6.10.255

most of the from(s) start with (b.  or n. ) then digits: 
n.4879.15139502 at badweathertomenow.info  and really look fishy.

So before I block the ... ahem ... block, what do you all feel about it?

todh