We stayed there on our first trip to the island, when it was Le Meridien. The area is beautiful, and the beach is nicely sheltered in a cove. We didn't find the road to be a problem, and left every evening to drive into Grand Case for dinner. We did rent a Jeep that trip, but have driven the road since then in a smaller car with no problems.
I can't speak to the resort, as we haven't stayed there since it became Riu. As you know, since you've been to the island in the past, St. Martin really doesn't lend itself to all-inclusive.
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