I think the value of a record weight will depend upon (1) the state of one's LPs, if one is using the weight to flatten them, (2) one's personal taste in listening (I like a "lively" sound, myself), (3) platter material, (4) turntable type (belt vs direct vs idler drive), and (5) probably tonearm and cartridge as well.
So far, I have never met a turntable weight that improves the sound, using a Notts Hyperspace, a Lenco with Boston Audio mat, or a Kenwood L07D with its stainless steel mat. The weight was least harmful on the Notts, but not that beneficial, either. On the L07D, the original Kenwood record weight squashes the life out of the music, IMO.
So far, I have never met a turntable weight that improves the sound, using a Notts Hyperspace, a Lenco with Boston Audio mat, or a Kenwood L07D with its stainless steel mat. The weight was least harmful on the Notts, but not that beneficial, either. On the L07D, the original Kenwood record weight squashes the life out of the music, IMO.