Greetings and Welcome Bert.
For the first effort, stick with what you have. Buying something that may seem easier is just spending money on something you may not really need. Standard track IMO is easier to landscape around. I do have some EZ track with some kits I purchased long ago. I found I could create the layout I wanted easier when I could control the curve radius. I use a lot of "flex" track.
The foam makes cutting streams into your scenery a little bit easier. It allows you to create depth below grade you can't do on just a plywood table top. You could paint streams, but it may not present the look you like or want.