Hi,

The Intel Composer 2011 or the Xtreme Edition Intel Composer XE 2011 should both enable you to optimize your code for performance, as they do contain many features including performance libraries etc. Of course, if you need other thread and memory error checking and advanced performance profiler etc., then you'll need the Intel Parallel Studio suite which contains those additional products completing the whole work-flow per-se. There are some additional features in XE edition that may not be in regular 2011 version (ex: Static Security Analysis). You can go over the following links that gives you more information on the products and you can decide what fits your needs:

http://software.intel.com/en-us/articles/intel-parallel-studio-xe/
http://software.intel.com/en-us/articles/intel-parallel-studio-home/

The link http://software.intel.com/en-us/articles/buy-or-renew/ should give you information on prices on the productsandreseller contactsetc.

Hope the above helps.

_Regards,
Kittur