Hi;
My unprofessional opinion is that if the swr is reasonable and one gets 
reasonable signal reports and there isn't a high noise level then the 
antenna works.  True I understand the pattern may be something other 
than the manufacturer intended but unless you have those three acres 
someone mentioned in an earlier post, antennas tend to come down to how 
much antenna can I do given the real estate at hand which is often 
inadequate.  The unfortunate part of all this is you really don't know 
how things are going to play until you put the thing up and give it a try.
just my two cents

-- 
richard