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I can't decide whether the gift is appropriate or I should buy a different one.

I can't decide whether the gift is appropriate or whether I should buy a different one.

Are both correct? Would you use the latter?

Thanks
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Both are clumsy. I would not use either one in written English.
Comments  
YankeeBoth are clumsy. I would not use either one in written English.

Could you please tell me how you would word it, and why they are awkward?

The 'whether' clause is correcly used after a verb of uncertainty, showing two possible choices. The two options are no single nouns, making it sligtly less lucid perhaps.