Actually I just checked it and mine has a 75 year transferrable warranty. Aside from warranties, you need to look at thickness and whether it is color through or just the top layer has color. Ok, I spent nearly $4000 on it for siding, housewrap and some insulation board and I could have spent 1/3 of that using the cheapest siding there was. However, the house next to me is 8 years old and the siding looks horrible. They are planning to redo it. They built their own garage and bought better siding for that and it still looks good. An 8 year old house should not look that bad.
In case you are wondering how what I spent compares to the size of the house, it is a 150 year old farmhouse, tall and with a couple additions. It took 27 square of siding. My estimates to have it done for me (with a quality siding) were around $15k.