I agree, start with your LBS. A smart person there will know that a proper fit to your "sit bones" is essential, and that softer is not usually better.
The advise about one person's dream saddle is the next person's torture can be very true. I have 3 almost new saddles that I'll never ride for that reason.
Lastly, if you are really riding that many miles each week you need a good quality saddle, don't skimp on getting a good saddle. A cheap one will end up being expensive because you will want to replace it.
If there is not a good LBS nearby then consider ebay. You can get a good quality used saddle for little money. That will enable you to try a few different styles.