you wont need spare engines unless you do have 175HP+.
There is definately a problem at the moment with guys spending way too much money on the Period 5 bikes and it's really not going to make them any faster. Like any class of bike racing, fast guys will be fast on almost any bike, provided it's set up ok, and slow guys will be slow regardless of how many $0000's they spend.
Thats why we all love bike racing