I forgot just how many good episodes were in season 3, man does Yesterday's Enterprise look great in HD.
The commentary track for that episode is also great, you really understand how overworked and how much pressure they were under that season, they had no idea they were putting out such great stuff at the time they were doing it.
Also just watched Deja Q, while most stuff looks great in HD the species down on the planet looked pretty bad. They were only ever meant to be seen on the bridge view screen so I guess they didn't try very hard to get the makeup perfect.