Actually,
1. A synthetic stock MAY get hotter in the sun. That's mostly a function of the color of the stock. A wood color synthetic stock will probably stay about the same temperature as a wood stock.
2. There are rubber overmolded stocks with will make less noise than a wood stock when bumped or scraped. Hogue is one company that makes such stocks. There are also other brands that have "quiet finishes/surfaces" on them.
3. A wood stock may be heavier, but a synthetic will take much more of a beating than wood without breaking. You could always weight a synthetic stock to match the weight of a comparable wood stock if this is important to you. Most synthetic stocks are hollow and you can epoxy weight into the cavity.
Add to this.
1. A good synthetic stock will not warp from normal heat or moisture exposure.
2. As mentioned above, synthetics are very durable. Hard to scratch, and hard to break.
3. Synthetic stocks tend to cost less than wood stocks.
4. Synthetic stocks are usually lighter [ a big plus to most people
]
Disadvantages.
1. Some people do not like the appearance of synthetics. However, for a rifle that will see heavy use, the synthetic stock will maintain its appearance much better.
2. The lighter weight of synthetic stocks can magnify recoil. See above about weighting the stock if this is a big problem.
Actually, I like the synthetic stock in heavy recoiling rifles. They are light to carry, but when I have to shoot them over the bench, I can fill the butt with BBs or some other weight to keep the recoil down.
Geez, next I will be writing a Soap Opera...As The Rifle Turns. 