Over the last couple of years I've started to see firmware upgrades take longer and longer on my routers (currently a 2866ax, previously a 2860Vac) with invariably the web GUI timing out after 10+ minutes and me having to hope that things have completed & reconnect / reboot.  Sometimes it's worked, other times (such as when I tried to move my 2866 to FW 4.5.0) it hasn't completed and twice now I've been left having to recover using TFTP.

Do others have these same issues?
What approximate timings do you all see when doing upgrades?
Does anyone go straight down the TFTP upgrade route as it seems more robust than doing it via the web method?