Digs01 was far from ep1's quality, but I enjoyed it anyway. It reminded me of hipnotic maps somehow. On the first playthrough on nightmare I tried to control myself from trickjumping to places where I shouldn't go. As Barnak already said, maps are too empty even on nightmare. I had no problems in any of the maps, some middle maps had ammo shortage though.
Digs02 surprised me nicely. I didn't think those textures would fit to quake, but it was perfect!
Digs03 was a bit of a maze, my first playthrough took 30 minutes. I managed to find all secrets but I don't know whether some of them are reachable without trick jumps.
As you may have got used to me doing speedruns on new maps, I'm not letting you go without demos on those maps this time either!
I did an easy skill marathon through the episode, finishing in 3:34, including the start map. The third map was the worst for me, as I kept missing the grenadejump many times.
I did the digs02 demo in 5 minutes, thus it's very sloppy. There is some potential for ogregrenadejumping + voreballjumping, but I couldn't be arsed to try them now. :)
On digs03 I did two demos, easy run and easy 100%. Again, here is some potential for double ogregrenadejump to bring the time much lower, like under one minute. In the 100% demo the last secret gave me problems. I couldn't find any other way to there. It may not be the best 100% route on this map, but try to enjoy of my demo. :)
Well, here are the demos then. Sorry for using filefront, I didn't have anything else in my mind. http://files.filefront.com/digs_demosdz/;7426150;;/fileinfo.html