We changed to an auto 2 cars ago when we swapped our Rialto-Passat unit for a V70 D5 auto-Lunar Lexon combo. Best move we ever made, effortless driving with or without the caravan, especially when stuck in traffic on the M6 or M1. Auto comes into its own with cruise control, just set the speed and relax, all gear changes are done for you. You can still use gears 'manually' and if I fancy a blast around the country lanes I use that option, obviously the gear change isn't as quick as a full manual, but you can get yourself into the 'right' gear for the situations you encounter manually. We just changed the V70 and the new car is also an automatic (7 speed!), wouldn't go any other way with a towcar.
However, the daily commute is a Mini Cooper S, manual - wouldn't have it any other way!!