All your preference. Just use the same grain to sight it in as you do to hunt.

It really depends on your hunting conditions. I feel that for typical woods deer hunting, one of the best overall for the .308 is the 150g bullet... plenty of energy to knock down the biggest bucks but a little flatter shooting and a little faster if you have to shoot at a distance or at running deer. If I were shooting prairie deer at ranges of 150-300 yards running, I would actually use a good 130 grain bullet to get the added velocity and flatter trajectory with less lead. For me the 180's in a .308 are for brush busting and perhaps elk. They are lumbering slow but penetrate brush and pack a whollop if you hit what you are aiming for. The choice is yours and they make all different sizes for a reason. If you can't decide between a 150g or a 180g, try a 168g... they are pretty nice for any conditions.

I stick to 150s in .308, sometimes 165.

Petzel's article on velocity in the current issue mentions the tradeoffs you are questioning, and it corraborates what you can infer from "kinetic punch" tables. The 180 retains more oomph at longer distances, while the 150 gets there faster. As Dakotaman suggests, the 180 is a better choice for larger large game at closer distance, or medium large game at longer distance. The 150 is flatter in its effective range, so experience with drop at different yardage is not as key to success. Personally, I don't buy the "brushbusting" point, because deflection is deflection, and it means you won't hit your point of aim.

180 gr will be moving pretty slow out of a .308 Win. I would only use it for moderate ranges. Might not expand at long range. 150g is a pretty balanced bullet weight for the .308 Win. I am drawn to 168g bullets so am starting there with my new .308. I am also looking at 130 gr Barnes TTSX. That should be moving fast enough to expand well on deer at longer ranges.

150/165- For deer size game.
180/220- For Elk/bear.

Couple of thoughts. What are you hunting? My old Remington 788 .308 Winchester sees active duty for whitetails and gets a steady diet of Hornaday 150 grain interlocks, fueled by IMR 4064, partly because it shoots them so well and partly because I like that weight for deer and where we hunt. I also am a bit suspicious of 180's for our little deer. Too, why don't you ask your rifle? It may be like mine and show a real preference for one particular weight, configuration, etc. You can't go wrong with a .308 either way. Good hunting.

I use 150 Gr SST because the accuracy is better in my rifle than any premiums in 165 or 180 grain. The 165 scirroco shoots pretty well but my rifle will scatter all 180 grain loads. SST 1.15" / 165 SC 1.65" / 180 GR 2.5"+ Winchester Model 100