I love my Spark from Target!! I posted this little "review" of the Duo vs. the Spark a few wks ago after some wonderful ladies suggested I check out Skip Hop ... HTH!
Ooh, I wanted to add for anyone else reading this thread that the Skip Hop Spark from Target and the Duo are pretty similar it seems ... some differences I've noticed today ... the Spark has bottle pockets on both sides (yay for twins!), the Duo has one bottle pocket and a cell phone pocket. The measurements on the Spark (in inches) are 14.5w x 13h x 4.25d (measured by me!) and the Duo 13 x 13.75 x 4.25 (listed on the Skip Hop website). The Spark's main pocket closure is velcro. So, the potential exists for me to dump the contents of the main pocket on the floor if I'm not careful, although the velcro closure measures 3.5in long, so it covers a good width of the bag, so dumping probably won't happen, but just an FYI. I do not know how the Duo's main pocket closes (magnetic maybe? That's what it looks like from the website). The shuttle clips are a little different - they look a little prettier and fancier on the Duo - but they operate the same way on both bags in attaching the bag to your stroller. The Spark in addition to the messenger style strap, has straps on either side so you can carry it more like the handles on a purse. The messenger strap can be detached on the Spark and the Duo. The Duo now has a little shoulder pad on the strap. The Spark is regularly $29.99 at Target and the Duo lists at $54 on Skip Hop's website. But there are various sales going on ... Ok, I think that's it.