Given that you want to use this in hot weather, I'd think about some of the options that are specifically for heat. I wore ds in 100 degree heat and serious humidity in our (regular) Tula. It wasn't terrible, but we were both pretty sweaty. As I said, I wouldn't recommend the Boba Air for long term carrying because the shoulder straps have no padding. (I did also have that carrier with me, which was okay for short term carries).
Here's a list of some other SSC options for water and/or hot weather wearing. I haven't tried most of these, so I can't actually weigh in on them. The Tula mesh isn't on here because it just came out. I'm not sure how hard it would be to get.
I will also say that we used a cooling towel when I was carrying ds in that intense heat. I had it around my neck. My one complaint was that it left all kinds of fuzzies on my neck. I think it may have helped some. It's worth a try and didn't cost too much. Just another idea for hot weather carrying. Hope this helps!
Beco Gemini & Toddler in Cool Mesh:
https://www.becobabycarrier.com/products.asp
Boba Air:
http://www.boba.com/boba-air#Black
Lillebaby Air Flow & All Seasons:
http://lillebaby.com/baby-carriers/view-all
Bjorn One Air & We Air:
http://www.babybjorn.com/baby-carriers/
Bitybean ultracompact:
http://bitybean.com/
Onya Baby Outback:
http://onyababy.com/outback.php
Kinderpack with Koolnit:
http://mykinderpack.com/
MJ Carriers with Fresh Mesh:
https://www.mjbabycarriers.com/
Connecta Solar
http://www.connectababycarrier.com/