You may want to check if the 902 will fit in the space. Since it's Walmart, it would be selling to the masses, who would have the smaller Dells/prebuilts. A custom case may not fit in it.
That link was just to give you a picture of what my desk looks like - I know the 902 will fit in mine. Actually there is quite a bit of room on top and on the sides so I think I will be good.