http://spf.pobox.com/wizard.html
While reading the "bad advice: Please stop publishing -all it is NOT
time yet" thread, I saw that Wayne suggested that any "ip4:" mechanisms
appear *before* "a" / "mx" / "ptr" mechanisms in the TXT record.
Apparently, that allows the record to be checked faster?
However, the SPF record wizard puts the "a" / "mx" / "ptr" mechanisms at
the start of the line. Perhaps this needs to be changed in the wizard?
Also (and I don't know who writes the wizard or takes suggestions), it
would be useful if the wizard would break-down any x.x.x.x/nn notation
and display the address range covered. (e.g. "192.168.108.0/24" would
display under the explain section as "192.168.108.0 to 192.168.108.255")