I've been to Morocco on 4 punting trips over a short period of time now,
As a punting destination, Marrakech has a lot of pros and cons, so it is not suited for everyone. If you want a cheap, chilled, relaxed and hassle free punting experience then this place is not for you.
If you don't mind negotiating, haggling hard, late late nights, lots of leg work, constantly looking over your shoulder and some crazy girls. You can have some great nights out there and Some gems can be found, but it's still bit of pot luck tho.
My last trip was tangier last month, haven't had the time to do a report on that yet. Might be awhile before I can tho.
I normally go with a mate or 2, for a better crack, otherwise would get bit boring. Im In Marrakech with 2 newbie friend's over a weeks time.