I've never heard great things about them as a long-term solution, but maybe it would work for you. A couple of things to think about: how wide is the resulting stroller? If you can't fit through doorways, you'll get frustrated to no end. And don't you have to take them back apart to fold the strollers, then reconnect them every time you take the strollers out?
How about exchanging your infant seats for Gracos? Using a single SNG and carrying one twin in a sling? Using a double like the BJCMD and just take the babies out of their car seats?
Have you tried the current double SNG with the Chicco seats? Maybe they work, just not officially. Actually, I thought that there was a post not too long ago on the multiples board about that... ETA one of those posts - you can search to see if there are more:
http://www.windsorpeak.com/vbulletin...d.php?t=309581
Single mom to
DS ("twice exceptional") - September 2002
DS - February 2006
DD - July 2009
DD - July 2009