As a hairdresser, I have used several of these products containing Moroccan oil that seem to have sprung up on the market in the last 18 months or so. I like them all, as generally they are light on the hair (ie don't weigh it down and make it greasy as most traditional hair oils and serums tend to) and smoothe the hair effectively too. However, the best on the market at the minute does seem to be the original, Moroccanoil.
The packaging isn't particularly eyecatching as it comes in a plain brown bottle with a blue label that to be honest doesn't quite match the price tag, but once you use the product, you will never go back - it is fabulous to use when blowdrying, straightening and to finish the hair. Just add a small amount and work it through the ends working up to the roots and it works a treat. Great for curly or coarse hair as it smoothes all those annoying flyaway bits that spring up. I use it on my hair every day almost, even if it is just to soften the ends - the hair feels amazing after smoothing a little of the oil though.
The price is a little prohibitive, but don't let it put you off because a little goes a long way, a the bottle is a generous size too. Highly recommend!