well, i hope i can help you relax....
its fine to want to get rid of the nuk, and its fine to do whatever works if your kids are ready.
i know my son (who is 28 months old) is NOT ready - if we dont give him the nuk, he doesnt cry and whine, he sucks his thumb. the whole point of us giving him the nuk is so he doesnt suck his thumb.. so until which point he stops doing that - he will have that nuk.
i want to ease your fears here: no matter what doctors say, its not going to harm your child to keep it a while longer, it wont even make that big of a difference with teeth either. people seem to push that its this horrible thing, but its not.
the best thing you can do is what you are doing. they only have it when laying down in bed. thats great! :D you are half on your way. i give my son opportunities to fall asleep without it and he does on occasion, and when he falls asleep and the nuk is loose in his mouth, i will just take it. its common that he wont ask for it the rest of the night. so in all honesty, if you are doing that, how bad could it be? if they only honestly have it in their mouths to fall asleep - thats what - an hour a day? its NOT going to hurt them in any way.
you do what you have to do. dont let anyone tell you that they are too old for it or that they are spoiled or their teeth will be screwed up or anything. most people spend more time sucking on other things (cigarettes, silverware, foods, candies) than your children do on their nuks, so its really not as big of a deal as it may seem :D
i personally think that you can wait it out as long as another year and just see how they do. supernanny has no children of her own.... so though she may have the developmental stuff down, she may be knowledgeable, and in every episode the problem gets worked out, remember, she has no children. she doesnt really KNOW what its like. everyone is like that until they have kids. we have definate ideas about how they will raise kids, and guess what, once you have kids... some things completely change. so remember that and consider the source when you are watching the show. i think shes great - but most of what i see in that show is training the PARENTS to raise their children, not as much teaching children how to behave differently. the families ive seen on the show dont know how to be the head of their family, to be the guidance and descipline that they need. im blabbing.... but i want you to know that you shouldnt feel aweful for any parenting choice you make - they are your kids and the only person who is responsible for them is you (and your husband of course) - so outside advice is only to be used when you feel comfortable with it.
anyway
so relax. its ok if you feel they need them longer.... it really is.