Mark is right on the money here. Use the loose powder. It is cheaper and you can custom the load a lot better. Pellets will give you a more accurate powder measure if you do not damage the pellets, but a good see through powder measure with a cut off funnel is the way to go.

As for the 150 grain loads.... I would not do it. You will not get accurate results most of the time. All you will do is burn lots of powder. Depending on the rifle throw powder away as unburned. Wear out your barrel in some cases faster. And your shoulder will hate you because of the recoil. Most of my inlines work best in the 80-110 grain range, depending on the projectile.

Get some Hornady XTP 240 grains and some Harvester sabots to start with. Put about 80 grains of FFg in the rifle and try them there. Work your load up in 5 grain amounts until the groups get real tight. Then adjust the sights of the rifle to that.

Some other good shooting loads out there are SST's, Barnes Expanders, Percision Rifle, and there are a number of conicals and powerbelts that will give you good accuracy.

With 90 grains of powder and a good projectile, there is very little any animal can do when hit with a well placed shot other then to expire. Good luck with your new rifle.