If you developing web applications and you don't use .net then InterDev is one of the best packages around. I know of loads of companies who develop web applications and they still use Visual InterDev.
I used interdev for a while until I got homesite. I find homesite much more useable for all around web design. Interdev is so clunky. I think Interdev has the same functionality, but it is just personal choice.
I think people who use visual studio are looking for the intergration. I never found it very useful when intergrating VB an C++. I just use homesite then bring it into Visual studio.