I would advise against using those since they operate on fields that are not indexed. If all you want to store is a uid and score pair you can use sorted sets like below.
//setting values
await db.sortedSetAdd('pluginname:users:customstats', [score1, score2], [uid1, uid2]);
// getting first 10 values
await db.getSortedSetRevRange('pluginname:users:customstats', 0, 9);