Traxxas usually makes some decent products especially for entry-level. The Traxxas boat called the Blast is only about $160. Not much more than you were already looking to spend. And they usually have pretty good customer support. Might be a good option to consider especially if your local hobby shop supports Traxxas products. Maybe show it to your kids and see if they like what it looks like. Usually if a kid likes what it looks like they were like using it if it has decent performance.