Honestly, why does 2 to 4 times slower mean anything? Why can't you cache? or write that really performance intensive part of the app in something else?
There aren't any numbers to back the idea that 2 to 4X performance means something. It's pretty easy to spend $5-10K per month on a single dev, thats a fair bit of hosting.
If the concern is speed of page rendering go with .NET, the JVM, or C++ it's much faster than rails or PHP will ever be. The trick is to use RAD/MVP to get you to that twitter like world of hurt. Then you rewrite in a faster language once you know what your product is like.
This brings up something I feel gets missed in a lot of language/platform discussions: a vast majority of sites on the internet are informational sites for people/companies and plenty of those are created by designers (non-programmers).
When you say it's easy to spend $5-10k per month, you're obviously thinking of a company whose business is the software, but this does not apply to most websites in the world.
There aren't any numbers to back the idea that 2 to 4X performance means something. It's pretty easy to spend $5-10K per month on a single dev, thats a fair bit of hosting.
If the concern is speed of page rendering go with .NET, the JVM, or C++ it's much faster than rails or PHP will ever be. The trick is to use RAD/MVP to get you to that twitter like world of hurt. Then you rewrite in a faster language once you know what your product is like.