No, it does not support TRIM. Currently the only rivers supporting TRIM are Microsoft's own storage drivers and Intel's.
Also, nothing currently supports TRIMing an SSD that is in an RAID array.
While the C300 drives are very fast, the build in garbage collection is not very aggressive, so without TRIM you will get a significant drop in write performance. I would recommend that, rather than running them in a RAID 0 you have them separate and spread out the IO load by installing stuff to both of 'em. This would allow you to use Microsoft's own drivers and so get TRIM.