Before jumping to any conclusions, I think it's necessary to know the rifle and barrel manufacture.
I also know that it's extremely important to get the Labradar set up and tested properly before shooting for data points. We shoot/test all day every day so we've seen the vagaries of the Labradar when it's not quite right. The instrument is not at fault, the way it's set up is.
Trying to compare loads to others when you're starting with a new barrel is basically fruitless. All the information you get will fall into a bell-shaped curve; those with higher than normal velocities at one end, those with lower velocities at the other end while the vast majority will fall under the middling bell shape. There are to many variables and too many folks who don't understand all of them, so the information has some distortion.
I'm sold on the performance of the Berger 135 Hunter for general hunting loads. We've even seen some 5-shot groups which are nothing short of exceptiona I shoot the 130 class bullets and will never go back to shooting any in the 140 class. I've been shooting a few of the 153s but so far the performance doesn't out weigh the expense, not at more than double the price.
Clean your barrel and do a proper break in. Skip the fire lapping.
Enjoy the process!