I had a chat with Roger Moy about Pro Sports.. his opinion was that they need more weight up front, he said the magic number for Pro Sports is 5¼ ounces.
Dunno what that is in new money, but if you look at photo's of the Lithuanian springer shooters (including Linas) with Pro Sports, they've all got barrel weights fitted (could well add up to just over 5 ounces from the looks of it).
But then again Nick Murphy is able to put his Pro sport to good use and he doesn't have barrel weights fitted. I mentioned to Nick about what Roger had said and he just shrugged his shoulders and said, mine seems ok.
So who knows