Contigo2063326 AUTOSEAL West Loop Vacuum-Insulated Stainless Steel Travel 20 oz. 1998256

How leakproof is this? If I lay it on its side, will it leak? What if I throw it in a bag (e.g. backpack, messenger bag, etc.)?

Is the interior stainless or plastic?

Does anyone know what the difference is between this model with "Easy Clean Lid" and the previous model with "Open-Access Lid"? Which is better?

Just bought these and soaked tops in warm water, coffee still tastes like plastic/rubber will this go away?