Honestly? In my oppinion it all depends what player and what team? So pretty darn hard to tell without knowing what team/pro and level?
But yeah - as a team - no matter how good you are, if you are on that level (not dissing it, I´m in division 1 as well!!!!) and get a good result with a pro guesting, it will most likely afterwards be known as something like "Yeah yeah they only came top-(insert whatever number you like?) due to having XXXX (insert whatever name you like?) playing for them....
Then it is solely a matter of wether you as a team appreciate having a pro guesting with you KNOWING this might be the "talk of the town" afterwards, or if you would like to try and achieve something on your own - or well at least without having a pro NOT asscociated with your team on a regualr basis on your roster?
As Far as Bullets/Lang/Mr. U goes.... Well can´t really blaim them can you? They did actually play the whole season for them, so to me that is actually quite fair - not the same as calling in pros for 1 event? In my book - well why not? And yeah - Bullets are actually all really descent players - they might not have gotten any top-TOP placings without those 2, but they are still a good team!
Again said - rules were followed, so yeah........ Did someone hear IPPU?