Transcend JetFlash 500 16Gb Flash Drive still can't replace my SATA 2.5 inch portable harddisk

I brought a Transcend JetFlash 500 16Gb Flash Drive and was wondering if I can use it as a daily software development used harddisk instead of my SATA 2.5 inch portable harddisk.  Well the flash thumb drive failed.  In fact, it took almost an hour and it's still in progress of getting latest from our subversion server.  Clearly thumb drive is very bad for getting a lot of tiny files.