My experience with foam wheels has been with ARF's.

A couple of years ago I got a Superstar 60. It came with the kind of wheel you might put on a park flyer. No ay would these stand up to the weight of a 60 size airplane.

Recently I bought a Hobbistar 60 and a LT-40. On both these aircraft the wheels are much more dense and IMO are good enough to use.

The wheels I got with a Ripmax Zephyr were pretty spongey too, but then the plane only weighs just over 2lb.

Having said all that I can't tell mch weight difference between a 3" Dubro wheel and a 3" foam wheel anyway. You won't notice it on a .40 size plywood box...