If you are staying north of town Flamingo Lake is very nice, if south of town I would venture on down to St Augustine and would choose North Beach RV. Just a few thoughts on Flaming lake, it is a very nice park and a destination spot. The area immediately south of the park is not the greatest but it has not intruded into the park itself. There is some very nice shopping and decent dining just east of there on I-295. Overall Jax has some interesting history and sights and is worth the visit but as in any big city some caution and situational awareness is required.