The yellowy brown ones, as you say, are latex. I have found with my breastfed babies that they like the latex better...I think it is because they stretch more like a mom's nipple, where as the sillicone holds it's own shape...also the sillicone is kind of slick and the latex is more "grippy" for lack of a better word. If you do try them, make sure you get the natural latch ones, not the old "square" shaped ones...those are kind of weird and neither of my babies would have anything to do with them.
Make sure you squeeze all the air out of the liner before feeding. Also it was suggested to me when I was having trouble with latch to feed the baby from a bottle more like they would nurse...ie...make sure they get a wide latch....if they grab onto the nipple shallowly take your finger and kind of flip their lip up so they are spreading their lips as far as possible and really grabbing onto the nipple like they would do when they are nursing. Also hold the baby more upright when they are taking a bottle so that it takes a little more work to get the milk out...this is also more similar to nursing.
I have been curious myself about those Adiri nursers....they really look like the shape of a breast, but they are expensive and I have not tried them myself. I have always had the best luck with the playtex bottles with the latex nipples. Any brand you try, make sure you get the widest version of the bottle possible (I know some of them have a regular and a wide version) and try latex when you have the option. I know alot of people swear by Avent bottles but my babies have not liked them and the nipples are SUPER hard....no stretch to them like a mother would have. Although they have a nice wide shape, that's as far as I would go saying they are like breastfeeding, and there are lost of other brands out there that have that similarity and others besides that as well.
