I've had my i5/8/256 laptop for three days. I'm upgrading from a late-2013 15" Pro (with a damaged screen).
I didn't migrate or use time machine, but instead installed the apps I use and copied over my documents folder and various preferences (such as for the terminal and my Firefox profiles). I also enrolled the laptop in the dev betas and am running 10.15.5 b2.
After a few hours, the machine was running well apart from opening apps. This was slower thann my 7 year old Pro, but once the app had loaded it was fine. I don't use any monitoring tools (for heat, fans etc) and my main tool is simply "top -o cpu" in terminal. I noticed that the machine was still busy doing various things.
Half way through the second day, having completed a Time Machine backup, and noticing that my indexing (and filevault encryption) was all complete, my app opening times are now normal.
The laptop isn't noticeably faster than the 2013 Pro but it is faster, and certainly fast enough for me. I haven't noticed the fans come on at all since the initial day after first boot. I'm on my balcony with the screen on max brightness, and it would be nice if I had the option to go brighter, but my old Pro was no better.
The keyboard isn't quite as good as the old Pro, but I don't mind it and I'm already used to it.
I have the screen resolution at 1680 x 1050 but at 50 years old I need glasses to use this unless, like right now, I'm in bright light. I'm probably going to stick with the default 1440 x 900 as I plan to buy an external monitor. Not yet decided between a 1080p 22" and a 1440p 24". I'll also buy an external drive, probably the Samsung T5 500GB. Both the monitor (a usb-c one) and the external drive will be bought with the substantial savings this laptop gave me over the 16" MBP which I was contemplating buying up until I read about this Air.
My only issue so far, and I'm hoping it won't be a deal breaker (I still have 10 days to return for a full refund) is that the camera is very close to unusable in low light. In the next few days I will have tried MS Teams and Zoom - I'll see how it goes. The camera is very noticeably worse than the late-2013 MBP.
As for the new stuff, I like the touch-ID and am happy there's no touchbar. I'm still trying to find a use for the force-touch trackpad. It seems to need quite a hard push (at mininum setting) and I find it no quicker than double tapping, which is a lot of what functionality it replaces.
tl;dr Laptop is fine, but the camera may be a deal breaker if it can't handle standard video conferencing in a typically-lit room.
EDIT: I'm running in 1680x1050 resolution during the day (my eyes prefer the lower resolution when it gets dark) and am not sure if I even need an external monitor. I had a MS Teams video call today and the camera quality was fine. It's still crap when it's dark, but it'll do. Unless I discover some new issue I'll be keeping my Air. I've ordered the Samsung T5 500GB external disk as it was so much cheaper than even a 256GB upgrade (from 256 to 512) of the internal SSD.
EDIT2: The feet on the bottom of the case are harder and much less grippy than those on my old Pro. This thing slides around my smooth table if I try to open the lid one-handed for example. Maybe they soften over time. Just a random observation.
FINAL EDIT: Unless I have my living room relatively dark in the evening, the camera is adequate. I've recently been synchrionising some stuff over from this Air to my old Pro and the Air is definitely snappier. It's a keeper. I installed fanny (because, you know, all everyone talks about is cpu temp and fan rpms) and I'm averaging at 50-55 degrees with zero fan. Interestingly, when doing some major copying, watching a video, and with an applescript running, the temp went up into the mid 80s and the fans (at their worst) were 4000rpm. I didn't notice the heat on my lap nor hear the fans over the video I was watching.
