SECTION [114AA. Penalty for use of false and incorrect material. - If a person knowingly or intentionally makes, signs or uses, or causes to be made, signed or used, any declaration, statement or document which is false or incorrect in any material particular, in the transaction of any business for the purposes of this Act, shall be liable to a penalty not exceeding five times the value of goods.]
Affidavits are declarations. In public interest, better to obtain a sworn affidavit for following reasons:-
An affidavit, has written statements that is really true and is sworn in front of legal testifying authority. It contains the written facts of certain events as the author recalls them into memory. Conversely, a statutory declaration is just an affirmed statement by its author or declarant. The claims or statements asserted are merely believed to be true.
When you want take a declaration which is other than statutory requirement, better obtain it as a sworn affidavit. If the declarant later becomes hostile or dies it may be more difficult to prove the authenticity of the declarant’s signature.
Don’t forget to see that whether the affidavit contains the verification by the person making it. http://indiankanoon.org/doc/654638/
Per chance you encounter any difficulty to get an affidavit, at least ensure that the person making the declaration signs a separate endorsement paragraph at the end of the document, stating that the declaration is made under penalty of perjury.