From what I can see neoscrypt is 3 times harder for the GPU and about the same CPU than the scrypt algorythm.
Perhaps because of the proportion of memory allocation to processing, it does run cooler. Totally efficiency is yet to be accessed.
The important question is security and neoscrypt is more complex than scrypt. i.e. each hash is takes more work, so it takes less hashes to secure the transaction, but each is harder to break.
The neoscrypt algo was designed to operate as hardened scrypt replacement. As I understood it, Ghostlander found that shortcuts in the litecoin scrypt usage made it easier to produce an scrypt ASIC, than it could have been.
This was not a mistake at the time, all Litecoin had to do was prevent Bitcoin ASIC from swamping their coin.
A lot of feathercoin members have made great efforts to move us over to GPU mining and have all the facilities available for interested parties to follow or get involved.
The move, away from scrypt, was made in a similar way, to prevent Litecoin ASIC miners from swamping feathercoins hash rate.
Feathercoin coin is returning to GPU mining until a feathercoin specific ASIC is developed.
One ASIC per coin, that could possibly be achieved with open hardware that is coded for feathercoin. That code is then included in a future soft fork release to make the ASIC operate only with Feathercoin. As opposed to design an ASIC to just do neoscrypt.
i.e. The change over prove we could switch to X-scrypt + ASIC with FTC key, at a future time.
