In general I do not like weights for stabilization. Not that they don't work but I have found that a reflex clamp can actually apply much more force that a simple weight. Plus weight will add stress to your moving parts that drive your TT (belts, motor, bearings, etc.)
Most reflex clamps work on similiarly. These clamps have several moving pieces the "twist" mechanism on the top engages a brass collet that grips the spindle in the center of the turntable. As you twist the collet begins to move back into the body of the clamp causing the body of the clamp to exert a downward force on the record. The result is the twister type clamp can perform a better job coupling th lp to the turntable, providing better dampening characteristics and can actually flatten a warped record. Check out the Clearaudio clamp.
I doubt that your DIY will cost much less, and most sellers will allow you to return the clamp if you don't like it How can you go wrong. Look
HereI've used both types, go for the reflex!!
Enjoy the vinyl!!