Hi Matt
Yes you can use it and there is NO alternate product that will do the same as AllergSTOP, however if not Authorised you cannot under any circumstances advertise the product or use the logo as this would be illegal.
As to being tied in for a period to maintain your licence and autorisation yes there is a minimum purchase require over the first 15 months, if you fail to reach this level then you would have to re-apply for authorisation in the following year.
What you gain by Autorisation apart from the training is a vast amount of sales and marketing support, discount on the product, benefits in terms of mutiple purchase of advertising and marketing material, leaflets, brochures etc , not to mention vehicle sign writting, uniforms, and all the other normal corporate stationary, including logo design and web site etc.
Hope this helps
Best regards Nick