I think it's the Kid MSD stuff I've been buying for my Obitsu 50cms. You just have to look at each piece you're interested in and evaluate it: Is it loose/baggy? Does it look like the material will stretch a bit? Is that bodice too "fitted" to match my doll's curves?
Using this shirt as an example (
http://www.dollmore.net/shop/step1.php? ... 0506095719)
They have the shirt modeled on a 43cm doll so the lengths will look okay (maybe a tad long) on your 40cm. The model looks slim and the shirt looks loose, so it should fit the 40 (which is rather slim) okay.It might be a bit large but large is better. Large can be made smaller, whereas too small can't be easily made bigger.
My stock 50cm Miyuki has a part of the purple/black leggings that the model is wearing. They are snug but fit her okay. Because of the construction (the black under fabric with the purple sewn over it) they have a lot of seams and don't stretch much so they won't fit my girl Anna Marie, who is a 48cm but has larger thighs. Some of their simpler leggings will stretch and fit her.
Now this little number (
http://www.dollmore.net/shop/step1.php? ... 0506095719) I wouldn't touch with a 10 foot doll stand. Expecting it to fit one of my girls would be very risky. Too much tailoring. It's made to fit a specific shape. The fabrics and the pattern weren't made to stretch. And a high price tag ($48.00), too high for me to risk a purchase. Unless I have access to the exact doll they are using for a model to compare with my own I wouldn't count on an acceptable fit.
And yes, the way Dollmore gives clothing dimensions (when they do at all) is kind of weird. One the second outfit listed above, scroll down and you'll find diagrams of the garments with dimensions given for them if they were laid flat. So instead of saying "bust= 18cm, waist= 16cm, etc." they give "flat" dimensions of the garment: chest width= 9cm, waist width= 8cm, etc. So you have to sit down and do some math to see if everything will fit.
It's a bit of work sometimes but you may have to do it depending on how much you want a particular outfit.