Yes. Luciene is the most important protein for muscle gain and fat loss. If you get less than 10%, they're cutting corners and you're not getting what you're paying for.
The one I'm using right now has 10.6%, it's a mix of concentrate and isolate though.
This particular brand has been on special offer and is retailing for less than 16 €/kg ATM. It's also quite soluble, at least on par with Dymatize if not better and infinitely more than Sci-Tec Ultragen. Dymatize Elite can also be had for about 17 €/kg anyway. Most often than not you can get better prices if you buy more than
If anyone's interested in the european area, including UK, east europe etc, just drop me a PM. Or if you know where to get good stuff at better prices