Today I found the following info in the net and surprise, no joke a perfect tuned 250 has more power with a higher rpm limit then the 300 (maybe it's cos of the better ignition like the first gen is also better then the newgen).
It says the thick line is the 250 (rev limit 13462 rpm)
This is the values (it's italian-ps, that means without aggregates - so at least subtract rd. 3 to 4 ps)
And this at least the document
And yes, the price for the race ready 250 is 41% more...