Choosing the right rode -- rope, chain-rope, or rope-to-chain spliced -- will depend on the type and size boat you're anchoring. Let's have a glimpse on them and their main features and characteristics.
Those simple rodes are typically made out of three strands of nylon. Being elastic, lightweight and inexpensive, nylon rodes are the preferred choice for owners of small boats. Their elasticity makes for great shock-absorbers for sudden loads caused by wave and wind. All-nylon anchor rodes tend to be pretty strong; however, a lack in chafe resistance inherent for rodes with chains make them less appropriate for extensive use and rough weather.
Three-strand line should be medium lay, which has more twists per foot than soft lay. This is particularly important for use with a windlass, as the soft lay strands can untwist and separate, fouling the equipment.
Larger boats with windlasses will usually opt for all chain rodes. Keep in mind that chain has very little elasticity, so pay attention to the rode not to become "bar tight" in high winds.
While useful and lasting, chain rodes tend to be heavy on the hands and on the wallet, and you'll also need a windlass. A windlass and all-chain rode may add a few hundred pounds of weight and adversely affect the performance of your boat.
As we've seen, both, all-nylon and all-chain, have their benefits and drawbacks. As is the case with human behavior, imperfections call for compromise, and a good compromise between all nylon or all-chain rode is to use a combination of both: a short length of chain connected to the anchor, with a long length of three-strand nylon line connected to the chain.
The only downsides of this combination (and you thought we've finally figured out the perfect rode!) is not being abrasion resistant over the entire length, and the inability in keeping the pull on the anchor horizontal, which is due to the weight of the chain.
Rope-to-chain Spliced Rodes
One disadvantage of the normal nylon-and-galvanized-chain combination rode is the interface between them, consisting of a shackle and a galvanized thimble. This combination rode is enduring, but the bulky connection adds a shackle to the system, which could possibly fail or lose its pin. One possible solution is splicing the nylon line directly to the last link of chain, which produces a sleek rode that stows easily, and passes through a chain pipe more easily than a splice/thimble.