It depends on your budget. Airplanemanager is very handy, but very limited. I interviewed PFM and they have a fantastic system that is fully customizable and very versatile. Their maintenance, crew and cost tracking is awesome. Their scheduling options are perfect. But, the cost is insane. Airplane manager is $60/month per aircraft ($100/month minimum) and PFM is $8,000-$30,000+ a year depending on the options you select.