I would suggest you look around check the finish inside the barrel the trigger pull and the way things are fitted together. Also it is a good idea to shoulder a number of different rifles when you find one that fits then check the quality, length of trigger pull and the way it comes up.
Also as Cayugad says don't worry about the 150 grain business start at 90 and work your way up, the way the gun groups will soon let you know what it likes.