Now i know guinea pigs are the most awesome pet! but thats the point are theyre any downsides too them? i know theyre a bit of maintenance and can stink (which is poor on the owners part) are theyre any downsides?

I've got two guinea pigs, and as long as u regularly clean out the hutch(completely once a week, and pick up poopies every day) and they have the correct healthy diet, u won't get any bad smell. My two piggies live in an inside two storey hutch and they don't smell at all :)
I can't find any downside with them, the only thing is that you'll need two, because otherwise they get very lonely and depressed. They need a big cage/hutch aswell for plenty of exercise. But that's about it :) hope this helps