If by some chance my parents let me adopt guinea pigs, should I get adults or babies? I just don't know. Let me know the pros and cons of both options and why you like one age range versus the other. Thanks in advance!
It depends on what you want out of your piggies. If snuggling is what you want most of, then go for a pair that is used to being handled and that you can snuggle with from the start. If you'd rather enjoy watching your piggies and don't mind if they are wiggly and can't sit still, then go for youngsters (or more likely a pair with one baby and one adult/teenager, as most good rescues prefer to rehome mixed ages for added stability when they have rescue born babies). If you want piggies you can interact with on their terms more than yours (more like a pint-sized dog), then look for big personalities.
You can always ask a rescue what they would recommend or leave it open until you have seen and met all their adoptable piggies to find the ones you really click with most. People that do the latter often come home with other piggies than they had reserved originally.
What I would recommend is to not so much go for age or a website photo but for personality. Pink-eyed white piggies for instance are often very laid-back snugglers and black piggies often have got oodles of personality, but they keep being overlooked - but of course, as we are talking guinea pigs - every piggy is unique, so not all piggies of one breed are the same. There is no hard and fast rule.
I have adopted piggies of all ages between babies and five year olds, and they have all given me joy in their own way.
Babies are sadly vocal and lively youngsters only for a comparatively short time before they calm down a lot as adults; that is something you need to keep in mind.
Some of the oldies have been longer with me than some of my younger piggies, so you can never tell; they also have a special place in my heart because of their personality and the zest for life that they have enjoyed their new loving home with.
At the moment I am also looking after a friend's 8 year old bereaved piggy that went depressed after the last of its same age companions died so she has the constant stimulation that she needs.
Personally, I like the mix; I also like having neutered boars as well as just sows - a bit of everything, in truth!