We also would have adopted an HIV+ child when we adopted our sibling pair. I've worked with several HIV+ children and have found it a rewarding, yet very challenging experience. When we were thinking about it, we didn't think much about what daily care and life would be like with an HIV+ child. Now, that I've worked with them, I know how much work that entails, and while I'd still take it on, it's really hard on both you and the child.
There's very few med options for kids and all of them are liquid (at least that was the case 3 years ago). And they taste awful. The meds one of our kids were on had to be given at EXACT 12 hour intervals and we were in a summer camp setting. There was nothing like thinking that you were going to be 5 min late getting the meds to kid - which then would get spit up or refused - and you would cause a resistance to one of the few drug options available. The parents had to think about what kind of programs or activities the children could be involved in because the med regime excluded the child from many activities as that need couldn't be met. The child didn't know of their HIV status when they were younger, and as they got older, it was really hard for them to be different. When this one child did disclose their status to their cabin mates, it was a really positive experience and we were so thankful of that.
Also, HIV impacts people in many different ways. I used to work in the AIDS field and many of the people I was lucky to work with were long term survivors. Many of the people who were involved in our work weren't actually able to work because of complications and long-term health issues. And, this impacted their longevity. All of this to say, is that while HIV is managed nowadays as a chronic illness, it does have a finite period. Your child could be really healthy and have a long life. Or, your child could be sick, develop full-blown AIDS early, and then die. You only get the time that you have with them which could be years or decades. After having lost so many of my colleagues to AIDS, I did have to leave the field because there was just too much loss (and I'm talking about the 2000s, not the 1980s), and I many of suffered from multiple loss grief. I think it may be important to process the eventual loss when considering adopting an HIV+ child.