[jtregunna]

It's almost always more efficient to use an existing CPU if it fits your use case than to design your own. Even if it doesn't, it is often more efficient (time wise) to adapt your use case to the hardware you have available, or write software to resolve the feature you want in hardware but don't have. Only the especially nutty build their own CPUs (I'm especially nutty too)

[monocasa]

Even if you're not designing your own, dropping a little Microblaze or NIOS down can simplify your design considerably.

[jtregunna]

Oh I know it can, my comment was more tongue in cheek not dismissive :)