I'm strictly an over/unders guy but since you're discussing a moneyline involving one of my favorite Major League pitchers, allow me to weigh in.
There's nothing "easy" about getting a victory over Eric Stults. While Jeremy Hefner looks very promising and undoubtedly has a future in a Major League rotation, there's always that tricky, tricky variable of entering his first ever big-league start. Mentally, that could do anyone in, just as it has done to some of the best pitchers in the game in their first career starts. Luckily, though, Hefner has drawn the lowly Padres as his first opponent, and I have confidence he'll do well.
Most importantly, the fact that this won't be an "easy" bet is that Stults is actually a very solid pitcher. Just as I've already written about multiple times this year, it BAFFLED me why this guy went two full years without starting a game despite looking pretty good in the Dodgers rotation in 2009. He has justified that point with two excellent starts (The first as a member of the White Sox on the road in Cleveland, which is no easy task. The second coming against the Angels, which is even harder), and with an assignment in a pitcher's park like Citi Field matched up against the sometimes-offensively-challenged Mets, well, this might be his easiest task to date. Of course, it never works out like that just because it indicates such on paper, but I still feel he'll handle himself well, as he's still on the return road to relevancy. If anything, you should consider my best bet under 8 in this game.
But don't ever say a win will be "easy" over Eric Stults.