In May my girlfriend and me went to Salto del Limon not on foot but on mules. We opted not for one of the ranches close to the village of El Limon (the Las Terrenas side) but go on on the road to Samana and take one of the ranches closer to Samana. There the road is a lot closer to the falls than near the village of El Limon. 'Ranch' was a bit too big a word, just a small farm with a couple of mules, one of the many along the road between El Limon and Samana. ours was called parada Franklin, but I don't think there is much of a difference between them. It took about 45 minutes by mule each way (plus about a 5 minute hike down to the waterfall), but judging on the walking pace of the guide it could be done in a good half hour each way in brisk hiking pace. The track passes through hilly terrain with lits of interesting vegetation, but no very wide vistas until you get to the falls.
Here is a map of the area with the location of the falls relative to the road:
http://www.saltolimon.de/Maps/index.html
I think we went off from about what is Rancho Espanol on the map. A pro of this route I think is that it's a bit shorter, as the landscape is not too spectacular (like the sanchez-las terrenas road for instance) and you'll have to return the same route as you came. A con might be that you don't have the spectacular view of the falls from the top of the last hills as with another route.