on beginning after start button on my rig, i get 20 fps for about 1 second then raises to 30/33 then 3 4 seconds later clean 60 fps, however are just around 200 objects on screen active i guess the static ones are not even taken any damage on my fps, however i cant say nothing about cpu utilization you should balance that so all computers should be able to play it, if you have a quad core machine and ur cpu utilization is more then 30% then its no good for older computers, now i know most people today are in the ultimate rigging with around 500 bucks, builds, but there are others that still using 10 year old tech(dual cores or even single cores.)
leaving all that aside, its one of the best retro games ived seen on forums in a while that also performs good.