Both Yukon listings describe double-wall vacuum steel construction, copper plating and a slider lid. Capacity is the verified reason to start with one size over the other: 20 versus 30 US fluid ounces. No controlled heat-retention comparison, dimensions or filled-carry test is available here.
Choose the portion before choosing the cup
| Routine | First size to investigate | Unresolved check |
|---|---|---|
| A regular coffee or tea serving | 20 oz | Whether the outside diameter fits your holder |
| A larger serving with fewer refills | 30 oz | Whether the filled cup and lid are comfortable to handle |
| Carry in a bag | Neither based on this evidence alone | No verified leakproof claim |
Jacob described favorable hot/cold retention and comfortable handling of the 20 oz cup. Bryan’s 30 oz comment praised its size, construction and insulation but supplied little detail. That is enough to retain the impressions separately, not enough to claim the larger cup stays hot longer.
The 20 oz lid complaint deserves its own check
Curt said the slider broke on his first lid and that the replacement remained tight, although it worked. This is a specific complaint on the 20 oz listing. It is not evidence of a failure rate, and the two captured 30 oz comments cannot show that its lid is immune. Inspect the mechanism before filling and use the tight-slider checklist if resistance seems abnormal.
