dd has been in her own room since around 6 months and we just switched her to a twin bed on the floor a couple weeks ago. she's 18 months.
she was fine in her crib but i'm due with #2 in may, want to sidecar a crib to my bed, and didn't want to own 2 cribs. she was pretty much sleeping through the night 7-7am and putting herself to sleep with a water bottle. she's also really independent and would often wake up and sing to herself for a while or i'd go in and she'd be comfortably lying there with no intention of getting out. so i figured she was ready and i wanted to do it so it wouldn't coincide with the new baby.
i was nervous about how it would work and kept putting it off (because she did love her crib...she would run up to it when she was tired) but in theory i was also ok with her getting out of bed, wandering around or playing, and then passing out wherever for a while until she figured it out (we close the door to her room.)
when it came down to it, it was so much easier than i ever thought i would, i probably got very lucky but it is possible for it to be a breeze. she was really excited about the bed and was jumping on it and we were fooling around on it all day. but when bedtime came she WAS a little apprehensive, tried to go to the crib, and cried when i tried to leave the room....a real cry, scared, not just bedtime crying. so for maybe two nights i had to lie with her for a couple minutes (not too long or else she'd just get super silly), the move to the chair, then slowly out. the second day was much easier, the third day i think i was able to leave right away if i left the door cracked, and then by day 4 or 5 i could just leave and shut the door.
naps were more of a concern because she is less obviously tired and more playful in the crib before sleeping so i thought she'd be up and out for sure but it ended up being much easier! went straight down the very first day!
i couldn't be happier that we went ahead and did it. she likes her bed, it's more accessible so i can always join her on it for a good cuddle or just to lounge around, and it buys me a little more time in bed in the am since she doesn't have to scream for me to take her out the second she wakes up. it's been so amazing listening to her singing herself to sleep or when she wakes up instead of shrieking for me to rescue her from the crib.
the weirdest part is peoples' reactions though. even though i am so so happy with how it's going the common reaction is "but she's so young!" and when pressed for why this would be an issue i can't get an answer. i've even been suggested to get her a crib tent instead (um....she had never even tried to escape her crib.) or that a toddler bed is an easier transition than a twin on the floor like we did (why? and why would i want a piece of furniture that i can use for like 1 more year...especially since the floor bed is working amazingly?!?) or to get a bed with rails. i don't get it.