The survey takes 2-3 mins and you get a unique $15 voucher code. It doesn't include shipping (which is $7.73 for all the items and postcodes I tried, incl WA) and no minimum spend.
Any item that's $15 or less you just pay shipping. Eg, you can get a Keep Cup for $7.73 delivered. Not bad.
T&C:
The voucher is valid for 5 days from time of issue. You will receive an email with the expiry date and time. Unused vouchers cannot be re-issued or redeemed after the expiry date. Each voucher code is unique and can only be redeemed once. The offer is only available for the first 1,000 participants. This voucher is for $15 only and is not redeemable for cash. There is no minimum spend amount when using this voucher. The voucher is valid for any product/s for sale on the Todae website, except shipping and related expenses such as shipping insurance. If less than $15 is spent when using the voucher, the entire $15 value will be utilised and the balance will be forfeited. There is a limit of 1 voucher per customer (defined as a household). Voucher cannot be used by any customer who has already used a Todae Survey voucher in the last 3 months. Todae has the right to cancel any order and refund any balance paid if this occurs. This voucher cannot be used in conjunction with any other promotional offer or promotional voucher, this includes earning RewardCentral points (even on the balance of the transaction after the discount) and affiliate rewards/commissions. The voucher is only valid for online purchases. Todae has the right to alter, amend or end the promotion at any time
Recieved an email saying that it is $20 now. I think the url you provided may be linked to your email