一个好的保温杯可以用很多年。

国内保温杯质量不稳定，批次差异大，代工质量好，自产反而差。

价格不贵，但效果不好。

如果不磕不碰，一个200块钱左右的不锈钢保温杯，可以用几年十几年，仍可以保证开水过夜仍然烫口的效果。

没有保温杯评定，我按销量和评价排序的美国亚马逊保温杯品牌和型号给你参考：
Zojirushi SM-KHE48AG
Udyr Vacuum Insulated 16oz Cup - Double Walled Stainless Steel Water Thermos
Sfee 17oz Double Wall Vacuum Insulated Stainless Steel Water Bottle Cup
THERMOS FOOGO Vacuum Insulated Stainless Steel 10-Ounce Straw Bottle
Vacuum Flask 16 ounce - Stainless Steel Vacuum Bottle - Light-Weight and Compact Travel-Friendly Beverage Drink Bottle - by Utopia Home
Cloud9 Vacuum-Insulated Double-Wall Thermal Stainless Steel Bottle With Tea/Fruit Strainer Contigo SnapSeal Byron Vacuum Insulated Stainless Steel Travel Mug
Stanley Classic One Hand Vacuum Mug
Contigo AUTOSEAL West Loop Vacuum Insulated Stainless Steel Travel Mug with Easy Clean Lid YaeKoo Insulated Stainless Steel Vacuum Flask Travel Mug
国内THERMOS，Stanley，Contigo比较多。

国产品牌则富光、哈尔斯较好。

保温杯不是什么高难度的玩意，任何不锈钢厂都能做，所以品牌多，出众的稀有。