Instruction: Given the user's review, identify the user's sentiment from the listed options. Answer using one of the options.

Input:
I've been buying Nissan thermal cups for years.  Everytime I try another brand, I am hugely disappointed.  All thermal cups are not created equal.  Nissan keeps its promise to keep liquids hot for hours.  It works even better if you pre heat it by adding boiling water first and keeping it in until you are ready to put your drink in.  I will never try another brand again, no matter how fancy the packaging.

Options:
A: very positive
B: positive
C: neutral
D: negative
E: very negative
Answer: A: very positive