I think it's perfectly reasonable. I got into a huge fight with an ex years ago over this exact thing. The way I see it, you've either got two choices- keep it and lie to him and pretend you like it when you really don't (in which case he wasted two hundred bucks) or just be honest with him and nicely tell him you appreciate the thought but it's really not your thing. I'd much rather someone be honest with me and let me know they don't dig what I got them than have them lie to my face and pretend they like it to spare my feelings. My take on it is, hey, if you don't like it, by all means get something else instead. If I'm buying a present for someone it's because I want them to enjoy it. If I goofed and got the wrong thing, I'd rather they go back and get something they like. That's the entire point of giving them a gift.

Not sure if it'll work out, but that's my take on it.