I also code very much with ASP, VB & .NET. I have been coding in PHP for a few years now as well. I have never had any need (at least in Web dev) to use anything else for *NIX. If it's the object oriented interface you are seeking. I would suggest using PHP classes. If you want that compiled byte code (which probably does run a bit faster ... maybe much faster. I just don't know! 😉), then I cannot offer any assistance.
As for 3rd party COM objects...you know, the ones you have to pay for! I have noticed you get them because ASP & VB cannot handle some type of Web task due to intrisic limitations. PHP, on the other hand, has a function for just about everything I've ever needed.
Cheers.