After much deliberation, I have decided to go with the Aluminum Sport model, Space Grey with black strap. I also really like the white strap look as well. I'm not going to pick a second strap up right away, but may pick it up in the future.
I definitely like the Stainless Steel look better, but I think after the initial excitement wore off, I came to decide on the entry level casing because:
1) As much as I really think I'm going to like and use this thing, I don't really know yet. It doesn't makes sense (to me anyway) to go in with a more expensive model that doesn't add any more functionality not knowing 100% for sure that I am sold on it.
2) I really think I am going to like the watch a lot and use it, but I also think the Apple watch has A LOT of room to grow. This first iteration is extremely dependent on your iPhone. I really think over the next iteration or two, they will add a lot more "independent" functionality to the Apple Watch (think GPS), along with possibly adding more sensors, or tightening up the accuracy of what's already in there. Also, possibly improved battery life, increased water proofing, etc.
I will feel a lot more comfortable dropping $700 or $800 on a Stainless Steel model once I have had a year or two of use under my belt, and knowing I'm getting a more refined version with iteration 2 or 3 in the future.