Agree with DB, there is nothing quite like it.  I like the tandem trip and I like the solo, but they are somewhat different species.  Solo may be the best opportunity to see some critters, as the human sounds are minimal.  Have had a weasel work the shoreline right past my feet, before it sniffed me and stood up with those beady eyes...   Solo offers the most freedom, along with the best opportunity to get in a pickle...