The plastic tank in the link isn't the one you want. It has a solid plastic cover with a plastic guard over the light and the screw that holds the plastic cover in place corrodes in a few months making it impossible to change the light. It also comes with a cr*ppy light which is hard to upgrade.
The tank you want is made of glass and has glass covers and a light strip that goes on top of the glass cover. The light strip can be retrofitted so you can have decent lighting on the tank.
I hope you can see the pic. Our server went down the other day and I am unsure if the pic will show up here. Let me know if you can't see the pic and I will see if I can fix it.
At any rate, the black tank on the left is the one you want. The blue tank on the right is a 2.5g. It is from the same manufacturer as the 5g you are looking to buy and is not the tank you want.