That is good news. As Dell is a very large vendor, you will find multiple revisions of a motherboard, or even totally different motherboards, in the same model line up. So it still isn't a 100% guarantee of compatibility. Check Dell's support site for any available BIOS updates.
The difference between low profile and full height cards at this price point are minor. The GPU is small, the memory usually only a few modules, and power requirements low. Basically comes down to cooling effectiveness and the default clock settings provided for the GPU and memory. A larger card is more likely to stay cooler longer and offer greater boost clocks. Bigger usually also means quieter, a tiny fan will make a more high pitched noise that will carry...