L.D.
I did NOT have a sit in stand - but DID by a Maclaren side by side double stroller and LOVED it.
The backs will recline, so at about @ 4 months I put my daughter in it - no problem. Before that, I carried her in a sling and pushed a single stroller.
The Maclaren is SUPER light, easy to fold up, and easy to navigate. Nothing is worse than having to mess with a heavy, awkward stroller when you ahve two small children running around.
It was not a problem not having a place for the infant seat - there was never a time I wished I had that instead of a sling or the Maclaren.
I chose NOT to get the sit in stand because it didnt look like the toddler could really be strapped in good and I didnt want him running off when my back was turned. Also, if the toddler gets tired, he can't rest because he can't really lean back. Its like a bench to sit on.
I bought the Maclaren used for @ $70 but, if I had to do it over, would buy a new one because I loved it so much.