That jumpseat was my commute for an entire summer and a half. It's quite comfortable up front. It's quite roomy. Very modern. Electronic checklists, advanced RNAV, all the alphabet soup. I'd rather ride on it than on the 737 I'm about to ride on for 5 and a half hours. The autoflight system and FMC are pretty good though it has a yearning to overspeed in VPTH descents. Sips fuel. I'd enjoy flying the thing.
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@killbilly said it's temperamental. It's a Bombardier product and it shows: lots of stuff that you have to CTRL+ALT+DEL on the regular, better engineering achieved through pilot procedures as opposed to the brute-force Boeing approach "of course you can start the engines in this wind, what are you, silly?", and a few other things that fall under "close, but not quite" or "wow, that's a limitation here?"
I had one ride home where a flight control computer was MEL'd and I swear to god the thing was floating a spoiler with how much shaking there was at cruise mach, but nobody else seemed to be terribly bothered. I watched another crew do an APU-to-pack-takeoff (I think that's what it was—my memory is a little hazy) and it seemed almost as complex as the terminal count for the Space Shuttle. But the ECL walked them through it nicely.
It's quite a modern airplane, but there are obvious places (to me, and for us) where it's "close, not quite" compared to some of our more established fleets. Example: For some reason probably related to money probably it's incapable of both takeoff data uplink (nobody at the Air Line has ever dorked up hand-jamming takeoff data, nope, not with multiple takeoff flap settings, multiple takeoff thrust modes and assumed temperature with that, nope, not even once) and automatic waypoint position reporting, both of which even the "classic" 757/767 can do around here. So, steps forward and steps back, I guess.
Then there's this, which, well, what in the frak:
Several in-service events were reported to Airbus where the flight crew inadvertently selected the autopilot while attempting to engage the autothrottle during the takeoff roll. Inadvertent autopilot engagement may result in early rotation that can lead to a tail strike, inability to climb...
safetyfirst.airbus.com
None of this should be construed as me pooping on the thing; quite from it, every airplane I've ever met has something you can point at and go "really[1]?" Just the stuff I noticed, even in my "I'm tired from crossing the pond" haze.
[1] N/A, Boeing 757-200