Hi Dezza,
Firstly, if you havent already done so, take a look at the tax opinion by greenwood & freehills in relation to this product.
Unfortunately, as you will see when reading their opinion, the application of tax laws in relation to DPAs is still uncertain.
Subject to certain assumptions dependent on your individual circumstances, I would be of the opinion that the interest on the Capital Investment Loan is NOT deductible under s8-1 as no assessable income can reasonably be expected to be derived from the investment during the period of the loan. Rather, the interest may possibly be included in the tax cost base of the delivery asset upon maturity.
The above is my personal opinion only, and is not to be construed as taxation advice. Please seek advice from a qualified tax professional.
Hyperion