The first time I flew a 787 last year I had a cold. I'm mildly asthmatic too so when you have a cold, just being able to breath without laboring is a blessing. Getting onto an airplane with the lack of humidity and higher altitude pressurization is probably one of the worst things you can do in such health(I had to go on a business trip). I ended up flying on the 787 and I actually felt fine on board. I remember talking to the crew about how great I felt.