bdj, in May ferries will not be full even on a Friday ... flying dolphins take 40 minutes to Aegina vs about 55 for conventional ferry (capacity over 1,000) , however I do recommend the latter. Dolphins are closed-in, and windows are salt-fogged, and view is minimal. On regular ferry y ou can sit out on deck & enjoy a wonderful view of islands, mainland, other vessels, plus small yachts ... on a sunny day, sit and watch the wake, a great way to relax.