I can appreciate your desire to have the freedom to control your schedule and just be with advanced divers/friends. I have my own gear but prefer to rent gear for students/visiting friends and not lug tanks or weights around. The Sameasan deal sounds pretty cramped. In the end it may be a bit more baht to stay "mainstream" but it is worth it IMO for the reasons already stated. Nice you have the choice.
Safe diving
Safe diving