OK I went through bottles soooooo insanely that I can give you some decent heads up.
We LOVED our vented bottles. Sassy Mam and Playtex Ventaire were our favorites. They made her spit up less, they are well made and hold up, and both are just great. The only drawbacks were that there were extra peieces with the bottoms being vented, so it took an extra few moments to clean them, and you need to have 'storage' bottles when out and when heating liquids. Youcan't mix powder in the vented bottles, you need to mix it in a storage bottle (evenflo classic bottles, 3 bucks for a pack and they have discs that turn bottles into storage) and pour it into the vented. I know it sounds like a pain, but it's soooo worth it! Sassy Mam bottles are much better with leaks since the bottom vent snaps into place... no worries.
Avent was good, but they leaked a crap ton unless you put the top on perfectly. Also the old ones have BPA. I've heard since they have changed their bottles- BPA free now, but i've heard they leak even more. Easy to clean, though.
Evenflo classics- as bottles, they are pretty darn good for the price. Extremely basic, but to be honest, i would have kept using them if i didnt get the vented ones as shower gifts. the price is amazing for the quality, and the replacements are cheap!
Even flo comfi- pain in the ***! daughter wouldn't drink from them, they bubble when you try to sterilize them. I wasn't happy!
parents choice- terrible! But we used these as those storage bottles for the ventairs because they are actually sturdier and leaked less often than the even flo
Dr. Brown- waste of money. not a bad bottle, but you can get just as good for much cheaper.
Nuby- this bottle would be great if it wasnt for the nipple design. I used the bottles for aw hile with the even flo nipples and they were fantastic, too. the ring is designed really well so it doesn't leak and helps with gas. plus i love the colors and they are just really cute, bpa free options. i wish the nipples worked easier because they have teething nubs of them, which would have been awesome if the damn milk would come out of them!
Playtex drop ins- what a pain. they were ok bottles, but i thought it was such a hassle to push the bag up and keep it up. if she stopped drinking, the bag would inflate unless kept upside down, and then i had to stick my hands up the bottle to try to get the air out all over again. i just thought they were too much of a pain to deal with. yes, even more so than the vented bottles.
Medela- decent. nothing spectacular except i liked the caps for storing breastmilk.