I've got a Grand Cru on the go for my Christmas brew. I intend to bottle it in 330ml bottles, partly because it's pretty strong

and partly because I understand they are also pretty highly carbonated. So, smaller bottle into a standard pint glass. Now, I've been collecting lager bottles from work colleagues etc and have most of what I need (mixture of green and brown), however, I've also been left with a couple of J2O

bottles. Now I'm not sure about J2O but I believe this isn't carbonated in which case I'm worried they won't be strong enough. What do you think? I've also been handed some Britvic 55 bottles which I'm sure
arecarbonated, but the same question applies. Will theybe strong enough?