If you have the time, it's well worth visiting this ruin. It has fine carvings on display, particularly the hieroglyphic staircase, with five 6m-wide steps, each with two rows of superbly preserved glyphs, climbing to the base of the royal palace near the main plaza. (But find out if it's currently visible as archaeologists may cover it up.) In addition, a number of stelae standing here are in excellent shape with clear inscriptions. Getting here, however, is a serious undertaking.
The best way to reach Dos Pilas is by tour (boat Q500, 4x4 Q800) from Sayaxché or by staying at the Posada Caribe and organizing a tour there, possibly by horseback. If not by horse, you'll be driven over a rough road to Aldea El Nacimiento (one hour or more depending on the mud), then you'll hike for about half an hour to the site. Camping is an option.