The 1 major side effect that turns me off cigars is the cigar mouth I get for 2 days afterwards.
People react differently to that aspect. Some have serious aftertaste issues for days, while others like myself only have the problem for a few hours. There are remedies -- brushing and mouthwash are the most effective, but the mouthwash is the most critical.
This stuff kills most cigar taste and odor in a few hours, if used once/twice within that time period. It's a two-part activated rinse that doesn't rely on alcohol and flavorings to do the work.