For the $20 that I paid for the full set (did not the include the pitching rubber strip), I'm very happy with the heaviness and quality of the bases.  Each base probably weighs a couple of pounds and seem very durable.....much better than the real thin, lightweight, flimsy base set.  On a flat gym floor, these will stay in place a lot better because of their weight.  They do a good job on the grass and are wonderful to throw in the trunk for possible pickup games with the kids (or their friends) or at a family picnic.  I guess if you really needed these bases to stick in the grass, I would recommend purchasing some 3/4" or 1" wide white webbing that's about 17" long.  Use the poly/nylon webbing and some spikes to hold the webbing down over the bases.  You don't want to puncture the rubber bases because that puncture is just going to rip bigger and bigger.  My boys are only 5 and 7 yrs old so these are just fine.  If playing in the grass alot, I may have like to see Franklin make this same set in a neon/construction color orange.  The orange color would help make the bases pop a little more in the grass, and probably make them a little easier to see.  If the boys continue show interest in baseball and get older, I will make the investment for a more durable home plate with the 3-5 spikes in them so the home plate is thicker/heavier and stays in place during batting practice.  One improvement that I would like to see Franklin make on these rubber plates is to manufacture some heavy-duty "tabs" on the outside of the bases.  The tabs would have small holes in them so that you can use small ground spikes to anchor the bases down in the grass.  For home plate - use three tabs, you could have tabs on the front corners and at the back tip.  For the other bases, you could use four, but at minimum, have two tabs on opposite corners.