I've been very happy with mine and found them a lot easier to fill than regular travel bottles because of the wide opening and easier to use because they're squeezable, whereas most low-cost bottles are thin but fairly rigid plastic, so it can be hard to get thick liquids like conditioner out. I've never noticed a weird smell with mine. Maybe they smelled when I first got them, but definitely not now. Plus I haven't had one leak yet - not something I can say for the cheapo bottles. I travel a lot, so they see a lot of use.
OP - I usually carry 2 (shampoo and conditioner) in my kippie bag because the 3rd (lotion) means I can carry fewer other items. But 3 plus a tube of toothpaste, moisturizer, some lipgloss and maybe a nail polish fit fine.