for the price, it is not a bad choice at all, as long as you can find a good motherboard.
Turbo Boost means, when you have some spare cores, those cores will be used to "help" other working cores, and have a boosted frequency. for example, you are doing something that can use only 4 cores with 2.6 Ghz, other 4 cores will not be used, Turbo Boost then can boost those 4 working cores to 3.0 Ghz