I dont want to drag this thread away from its origins but i'm quite a strong advocate of auxy outboards....
True, we do use our rib to venture somewhat further afield then the average rib user but never the less, even if we stayed in the sheltered coastal waters near where we live, we would still use one.
An auxy outboard will give you more than just the option of getting back to port, it can be used to assist in various other situations.
I have lost count of how many times the inshore lifeboat gets called out simply to recover a pleasure boat that suffered engine failure. On many an occasion, i have seen pleasure craft drift into busy shipping lanes (West Brambles in the Solent) causing a real headache for commercial traffic. If they were equipped with an auxy, then at least they could have cleared themselves from the path of oncommong container ships, tankers etc...
If (god forbid) we suffer engine failure when far from the coast then i know that, even if i can't get myself back to port, at least i can put the nose into the swell and stay 'comfortable' while waiting for help to arrive.
We also use our auxy for 'quiet' navigation through canals, rivers etc....its nice sometimes to be able to hear the vildlife around you while gently meandering along at 3knts....quite theraputic actually (i must be getting old!
'Seastart' is good, i just wish more people would use them but i appreciate its an extra cost to what can already be considered a 'costly' passtime??.
Incidentally, over here in France, if the lifeboat goes out simply to recover a driffting pleasure boater then the owner of the boat gets charged for the service (i believe its a minimum of 80 euro's). If the RNLI adopted this philosophy then maybe people would use either the likes of 'Seastart' more often or make sure they were better equipped to go to sea. (people STILL going out with no VHF or flares etc...)