I have owned and loaded .30-30 ammo for cousins, brothers, neices, and myself, for about 40 years. When it comes to purpose designed factory loads for the .30-30, Winchester PP's and Remington Core-Lokt's are as good as it gets. Handloading Hornady, Speer, and Sierra 150/170gr bullets, they work as well as the factory stuff, and usually shoot just as well. But not actually any better.
The difference between 150gr and 170gr bullets might be apparent on a fair size black bear, or to the guy who actually uses his .30-30 for elk. Which a surprising number of people do.
On deer, it won't make a bit of difference. Power Points, Silver Tips, FP, HP, etc. they all work about the same. Just fine.
I keep an inventory of bullets for my .30-30. Sierra 150gr/170gr, and a couple thousand Magnus cast for fun shooting. On the rare occassions I've purchased factory ammo, (like the time I arrived in Maine, and left my ammo home :-(, I bought Winchester PP's). They shoot to the same POI as my handloads. But I don't think there's much difference, if any, on game.