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

Input:
Tiffen, always being my number 1 choice. At larger f-stops and wide angle (18mm or so) I get some vignetting - although it is stacked on top of a Tiffen UV filter. Wishing I would have purchased the 'lower profile' filter.

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