I also believe that Mayweather's going to win, but I have doubts he'll get a stoppage. He'd have to hit McGregor with a TON of punches, as he was never a big power puncher. The only chance for McGregor to win is by KO, and that's a very big long shot. I predict it will be a very one-sided win for Mayweather (probably by an easy unanimous decision).
Boxer Paul Malignaggi, who had been brought in to help McGregor for the fight, has said that McGregor's boxing is a joke. I don't know the veracity of his claims vs. the McGregor camp's. BUT we have to remember: this is NOT a boxing vs. MMA fight; it's an MMA fighter (albeit a top-notch one) going up against perhaps the best P4P boxer of his generation, in the boxer's own game. Ironically, McGregor will become the richest MMA fighter ever, by losing to Mayweather.
But we'll all know what'll happen soon enough.