Thinking About Getting An Italian Greyhound?

I currently have a 5 month old male Chihuahua, he is fully vaccinated and set to be neutered within a month. He is great, 99.9% housebroken, knows some commands, is less bark-y than most chihuahuas and loves people and other animals. I have been thinking about getting a second dog. Another chihuahua is what I will most likely get, but I have also always loved Italian Greyhounds. My chihuahua will be about 5lb when he’s finished growing, so I know the Italian Greyhound would be bigger than him, but I don’t think that will be an issue.
My question is what are the main differences between the two? I don’t just want googled answers, I have done a lot of research, I want more first-hand experience if possible. I have read that IGs don’t like cold weather, rain, can be hyper and fragile, and are very hard to house train. However, I have heard most of that about chihuahuas, too, and have found that I haven’t had many problems. If I have been fine with a chihuahua, should I expect a tougher time with an IG still? Or should I be fine?

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