Fully agree with CoinHoarder.
The peoples with pay for VPS and mine PrimeCoin it's botnet's or serious miner's? My opinion - they serious miners.
IMO botnet's can't take control of PrimeCoint network until serious miner's with VPS mines PrimeCoin, because diff is to high and computers which controlled by botnet's in 80% cases it's a regular home users computers without much CPU power.
rdebourbon is working on a primecoin miner for the parallella (parallella.org). It is a $99 computer (essentially just cpu and cache on an ARM architecture) that can be infinitely parrallized. I think this may be the ideal primecoin miner by a $/XPM mined basis