Ergo ROCKS!!!! You will LOVE it! Promise!! I have the original one, so not the sport one.... it looks better I reckon. Check out their websites for comparisons or maybe a BB member will have tried out both and can see your post to add to it. I got mine with DD1 when she was 8mths (regretted not buying it sooner though let me tell you!!!) wore her in it until about 17mths..... stopped because I became pregnant.... and yeah she was walking everywhere etc.

I am going to start using it for DD2 in about a month seeing as she'll then be 4mths old