The things you need to consider for an appropriate cage for guinea pigs are size and how waterproof the materials are. The most important thing is that the cage is large enough for the number of guinea pigs you wish to house in it. If you want to house a pair of guinea pigs you should be aiming for 10 square feet of space, this must be one level multiple levels do not count as guinea pigs need flat open spaces to run.
When using wood you must make sure that any wood within the internal sides of the cage are protected by something that makes them waterproof, guinea pig have a habit of backing up to urinate and can also spray urine on the sides of the cage when annoyed, and you don't want urine to be able to come in contact with unprotected wood. You must also make sure there are no exposed edges of wood, soft waterproofing (such as a shower curtain), and/or glue/tape where they can reach as guinea pigs will chew on anything they can, particularly when they want their vegetables, and for some strange reason seem to greatly enjoy eating things like tape, soft plastic, and shower curtains if they have the opportunity to do so.
Here is a cage made from mostly doors and coroplast (if you don't like the look of grids you can use plexiglass/clear acrylic instead which I believe was the original plan of the person making this cage).
https://www.guineapigcages.com/foru...Cage-is-complete-and-I-love-it!!!!-(pictures)
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HollyG that cage you have linked is an okay size for one guinea pig, but it is a little too small if you want two. Not everyone has only one guinea pig so that particular cage may not suit everyone's situation.
For anyone else interested in getting a cage from amazon but need a cage that can fit two guinea pigs here is a link to another cage on amazon that is a good size for two,
https://www.amazon.com/Ferplast-Rab...8&qid=1530322636&sr=1-16&keywords=rabbit+cage I can't currently find any that are bigger so two guinea pigs is the maxium you can house in any amazon cage for now unless you can somehow connect multiple cages together.