If you search the post, there are who complain that 30 amp service has given some trouble if the RV has AC, Microwave, and Electric Hot Water. This is usually cured by switching the refer to propane, or turning the AC during Microwave usage.
Just for info, I have only seen 50 Amp service if the RV has 2 AC units, or is a park model with washer/dryer, and larger electric only water heater. If you plan to ever install a clothes dryer, you will need 50 amp connection.
2012 Ford F250 ext. Cab 4x4
2002 Jeep Wrangler Sahara
2008 Yamaha V-Star 650 Classic
2008 Work and Play 18LT