One thing that I really wonder about when I read that PPC hardware are so expensive is, what did your Amiga cost when you bought it? Did you get it for free from mom or dad? My a4k wasn't cheap when I bought it, damn expensive actually but it was SO worth it. Then you can imagaging what it has cost to change CPU cards up to the CSPPC which is probably the most expensive hardware that I've ever bought for it. Elbox tower with PCI-slots (the second tower that I bought), FastATA-III, GoldenGate, Voodoo 3, Voodoo 4, SB 128, CD-burner, RAM and so on. Let me tell you that my amigaone are A LOT cheaper compared to that and it runs much better too.
What I don't buy regarding the "it is two expensive" is when the same people upgrades their PC every 6 month, buy an iPhone, flatscreen TV etc etc etc.
If you are a die hard amiga fan but want... I don't know what... too expensive, I don't believe in that as a reason. I can do anything in AOS 4 that I could do in AOS 3, only better so why not? And regarding speed it's faster than any classic machine too anyway.
That arguement doesn't really work because the Amiga was up to date back then. It was in par with or superior back then. People are saying it's expensive now because we don't want to spend $800-$1000 for a motherboard that is 10 years out of date technology wise.
People spend a lot on classic stuff because of the nostalgia of it.