I assume many folks frequent this site to buy fish/inverts and also frequent the boards. If you can buy the same animal locally, check for disease, eating etc, why would you purchase something you have never seen?
Many folks live in small towns where a trip to a fish store and the nearest big city can be quite lengthy. Factor in time, fuel, etc and purchasing something online is a better allternative from a csot/time factor.
If I an unable to see the animal, I would at least like the oppurtunity to chat with someone regarding the animal they will se sending. How long have you had it? What is it currently eating? Etc, Etc.
If you cannot do this then you are left to only guess what you will receive and the shape it will be in. Is it eating? If so, what is it eating?
Sites offering guarantees of days will certianly be carful at what they ship but you never know if someone is "having a bad day" and they take it out on your order.
One problem I have with most guarantess is that they will give you a credit on the cost of the animal but you will have to eat shipping which can be more then the original cost.
The best approach would be to pool and order from this site where you get free shipping if you purchase 79 bucks or more, . It is not really free as a 10 dollar additional charge is levied...still a good deal.
If this is not possible then you most buy from reputable sites offering gurantees beyond the opening of the box and hope you don't have to pay the shipping twice.
Even with shipping, this site is still cheaper then the one lfs store in my small town. ..on most animals.