Bottle fan here.
i get camelbacks at work (actually with a handy wee pull through cleaning kit, never seen anyone using it mind
). Happy enough using a camelback in strange countries that lack refill points/burns, but in Scotland I rarely struggle to find water
Camelbacks just weigh to much for my liking, especially when full & I just can't see a reason for carrying that much water here, there nae handy for filling or checking how much is left etc. I also find that each time you take a drink the first few mouthfuls have warmed up in the pipe, eventually the whole bag warms a bit, much prefer freezing and fresh from the burn. Not really a huge worry but im just not overly keen in having a big bag of water in beside my doss bag/clothing/stuff
I tend to buy a wee platic bottle (maybe two) prior to setting out and refilling it on the move from burns, most of my bergans and day packs have easy access pouches so you can reach it & put it back on the move, the one that doesn't have pockets has bungee cord holders on the shoulder straps, even easier to access.
I think my record for 1 plastic bottle was a 10/11 day trip, it was pretty goosed at the end though, just be carefully not to mix it up with the bivi bottle