I am not sure which comparision you want to make.
For example, a 80Gb WD IDE drive with 8Mb cache is ~ £37.
For only an extra £30 (at ~ £66) rather than the extra £60, you can get a 250Gb WD SATA II drive with 16Mb cache. That would be worth it for me.
Also, Seagate have a 300Gb SATA II drive with 16Mb cache for £81.
There are others to choose from.
For example, a 80Gb WD IDE drive with 8Mb cache is ~ £37.
For only an extra £30 (at ~ £66) rather than the extra £60, you can get a 250Gb WD SATA II drive with 16Mb cache. That would be worth it for me.
Also, Seagate have a 300Gb SATA II drive with 16Mb cache for £81.
There are others to choose from.