#1 - congrats on the weight loss. i went from 280 to 180 myself and know how good you must feel!

#2 - i have had the 7.2, the 7.3 and the 7.7 within the last 3 years. between the 7.2 and the 7.3, i'd go with the 7.3. as others have said, it's lighter and it's perfect for working out! it's more expensive but you do get better components too. it's a good trade off instead of going crazy and getting a 7.5+

cheers,
-sh00k