Wow, I really enjoyed this set of levels. It took me over five hours (argh!!), but I survived, playing keyboard only.
I think I spent half that time or more just getting lost in maps 08-09.
Overall, very enjoyable, with just enough devious moments to keep me paying attention. I took heed at the warnings about dying to the vortex on map05, so seeing that put me on edge. The pitch black cyberdemon ambush on map06 was what really solidified my jumpiness, though. After two levels in a row ending with evil traps like that, I was expecting something similar in every level thereafter, though nothing else quite as severe as the map06 ambush occured in any of the later levels, IMO. Great use of tension putting those traps in the middle of the episode, they kept me wary long past the actual threat itself.
I had to deal with mad lag in glboom+ on most of map08, I guess my laptop's shitty gpu wasn't cut out for running through those huge open areas in the middle of the city. Lag aside (and getting lost aside ;P), I think that's my favorite map in the set. I almost gave up on trying to figure out how to get at that secret BFG until I remembered those blue keycard bars in the basement.
To be honest, I think I lucked out quite a bit. I'm not the most careful player so there were plenty of close calls. I was particularly inattentive / an idiot on map05; I wasted the radsuit and almost blew it having to go back through the lava unprotected. I was also very fortunate at how the one cyberdemon and the mastermind just before the end of map08 decided to infight while i was so close to death.
Anyway, great use of eternal resources, thanks gaspe for the great design and fun adventure! Now that I know what to do on the last two big maps, I'm eager to revisit this wad at some point in the future and try for a better time.