I bought the Zojirushi thermos bottles per recommendations on the Internet, but found that the silicon seals take on the smell of coffee and/or tea very easily.

I bought the Zojirushi thermos bottles per recommendations on the Internet, but found that the silicon seals take on the smell of coffee and/or tea very easily. And once the smell is on them, it's impossible to remove. While Zojirushi does sell spare parts, the cost is usually not worth it.