Ive been off Googling hot pixels and the like and im more knowledgeable about the subject than i was 30mins ago...
Seems its a very common problem and to be expected with exposures longer than around 5secs.
Makes sense really as the sensor heats up over time.
Im sure you guys know all this anyway.
Interestingly two identical cameras on the same settings can create different results. One might have hundreds all over the frame whilst another hardly any. Guess its luck of draw on how good the sensor happens to be in any camera regardless of cost.
The noise reduction does work on the E-300, ive not noticed this with my FZ38 but i guess its so processed that its all done by default so you get good results.
Maybe its not so bad after all then, just normal for a 5/6 year old camera.
Ive tested it some more and there are 1000's of them, looks like a deep field night sky shot!!