I'm in the same boat & would love to get Valco Triple Stroller- It's a twin stroller (valcobaby.com) and you can buy a toddler seat attachment. My friends have it- and it's AWESOME! You can convert it to twin only stroller, it fits through doorways, it has the ease of movement of a single jogging stroller and turning is a breeze.
My girlfriend had a Joovy sit/stand triple stroller that was great for her three kids if you are moving forward in a straight line. It was very heavy with the kids and difficult to manage at the zoo or if you needed to make any turns- she was a lost cause if a wheel ever got off the sidewalk.
Good luck- I'm due in March. Can't wait to introduce my son to his new sisters!
P.
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