Opinions: Using compact flash cards for backups of photographs instead of an external HDD

With the complete failure of an expensive and brand new external hard drive (see one of my other posts), I am reluctant to purchase another for use as a backup for my PC. For the cost of another drive (about $150 US,) I could purchase several compact flash (CF) cards. A check of my PC this weekend revealed that one, 32 gigabyte CF card could store nearly one year of shots in RAW format. Is it a good idea to use compact flash cards as a backup for PCs?