Aquafin is a waterproofing agent that is applied under a plaster finish to waterproof the gunite shell. It is not a stand alone product. It works well as it does not repel the plaster finish and provides another layer of protection from leaking.
Any of the three PebbleTec (Tec, Sheen or Fina) products are worth considering for longevity. 3M was discontinued last December and is no longer available (and for a reason!). The stuff sold at NPT is sold to any pool guy, and requires nothing from the purchaser by way of training. In other words, they are selling a product and don't care how it is applied or by who (I buy a lot from NPT, so I am not bashing them, just stating facts).
If you want a 10 year product, get plaster. Color adds (on average) $400-$500 per pool. If you want a longer life expectancy, and can afford PebbleTec, get it. It is worth the extra money and the training and company support, should you need it, down the line (BTW, I do not work for PebbleTec!).