Most common questions our readers ask our experts

Are the dates on soft-drink cans expiration dates?

They're "best if used by" dates. An industry rep we spoke to said there's no safety risk in drinking sodas past that date, but sugared sodas might taste syrupy as they lose carbonation. (The bubbles help neutralize sweetness.) The artificial sweeteners in diet drinks degrade over time, leading to the opposite problem: too little sweetness. Store soda in a cool, dry place away from direct sunlight.

I have component-video cables connecting a Comcast HD set-top box to a 720p TV. Will I see an improvement if I switch to an HDMI cable?

You won't see much improvement in TV picture quality; a 1080p set might benefit more, but not a lot. You need an HDMI cable to get a 1080p signal from a Blu-ray player or upconverted video from a DVD player. Otherwise, don't bother redoing your setup.

My car insurer raised my premium because my credit score dropped after I opened a credit-card account. What does one have to do with the other?

Insurers say the way you manage your finances predicts whether you’ll file a claim. We’d like to see that practice banned. In the meantime, boost your credit score by paying off card balances and fixing errors. To find the best deals on car insurance, see Save on car insurance.

A repairman told me that high-quality furnace filters impede airflow, making the furnace work harder. Is that true?

They don't make a furnace work harder, just longer. High-efficiency filters are designed to trap smaller particles, so it's more difficult for air to get through them. In our airflow-resistance tests of whole-house air filters, also known as furnace filters, we found that some are better than others. Follow manufacturers' recommended replacement intervals or replace high-efficiency filters after finishing tasks that disperse fine particles, such as sanding.

My dealer insisted that I sign an arbitration agreement before closing the deal on my car. Is this customary?

It's common, though by signing you could be giving away your right to sue the dealer or automaker, join a class-action lawsuit, file a claim under your state's consumer-fraud or lemon-law provisions, or even appeal an arbitrator's decision. If you see such a clause, find out how it affects your options. If you don't agree, ask to have the words eliminated from the contract or buy the car elsewhere.