Could anyone here who has had both Camargue and Rosso Selvaggio rices tell me about how they compare? I'm not sure if they're basically the same thing or not. Thanks.
French Red Rice (Riz de Camargue) and Italian Red Wild Rice (Riso Rosso Selvaggio/Selvatico) are each names for multiple, significantly different varieties that might, or might not be similar enough to substitute for each other.
Camargue is merely a region in southern France that is well known (among other things) for producing mostly biological wild rice varieties, or Riz Rouge de Camargue, but these can be of different grain shapes and have different preparation times. Wikipedia is quite blunt in describing this Camargue rice and fails to mention there are more varieties that are sold under the same name. If there is a new (non-wild) variety I wouldn't know, but Wikipedia seems to suggest so. Personally, I've used and eaten two different wild red rice varieties from Camargue (long-grained and short-grained), both with different suggested cooking times (42 and 36 minutes respectively, if I remember correctly), but they were of quite similar taste (the short-grained one being only ever so slightly more bitter than the long-grained one that is slightly sweeter tasting).
What you name Italian Red Rice (Rosso Selvaggio) is also a name for multiple different varieties of Italian Red Wild Rice (Riso Rosso Selvaggio/Selvatico), that might have different preparation times, grain shape, and what they taste like might also be slightly different. Just to be clear, Selvaggio or Selvatico is Italian for wild, I'm not insisting on comparing wild rices just to compare better with your French selection. They're grown in multiple regions of Italy. Some claim biological production, while other producers are cheaper and can't claim that (probably due to being grown in areas that are known to be still too polluted, or the land it grows on wasn't classified to be suitable for biological production for other reasons, such as the use of pesticides in recent history). I've cooked with many different 'Italian red wild rice' varieties, and they suggest preparation time from roughly 30-45 minutes. These 15 minutes of difference might be significant enough not to be suitable as a direct replacement in your recipe.
Both Riz Rouge de Camargue (Camargue, France regional red wild rice) and 'Riso Rosso Selvaggio/Selvatico' (Italian for wild red rice) are thus of genus Zizania, or simply wild rice. Since there are many types of wild rice grown both in Italy as well as southern France region of Camargue, with more than one variety having red grains, and are usually further classified by their grain length (such as 'long-grained', 'short-grained',...) and grain color, it is thereof impossible to say (based on provided information), if these two rice varieties would be 'basically the same thing'.
I could assume with much conviction (based on experience with both cooking with them, and later eating in risottos, rice with pancetta, filled zucchinis,...) that they would be directly comparable for recipes requiring one of the two, if they compare visually and their packaging claims same cooking time.
Then again, they would be grown in different regions with possibly different climate conditions (saying something comes from Italy doesn't really narrow it down enough for us to know that, but some Italian areas would have comparable conditions to those in Camargue, France, while most others wouldn't), and that alone can make for a big difference in its tastiness.
TL;DR - My suggestion would be to read their instructions and check that their cooking times are similar enough not to cause other problems with your recipe, but most people with less discernible palate probably wouldn't be able to taste any difference between the two in the same recipe.