I loved parts of it (the compassion, the kindness and the performances of the actors playing Hannah and Dougie).
Like other posters, I found Kev a really jarring presence, introducing a completely incongruous coarseness that seemed to belong to a different show, and spoiling every scene he appeared in. I got the feeling he was doing the job previously played by Finchy in The Office or Greg in Extras: the obligatory unsympathetic character so we had someone to loathe.
The real revelation for me was Karl Pilkington. He was totally convincing and incredibly natural.
Pretty much what I thought (having seen the pilot and episode 1 for the first time today).
Dougie and Hannah do stand out, Kev appears to be there just to provide a hate figure - which seems to have worked!
As for Derek, RG is far better than i'd expected after reading some of the posts on here, and seemed to have toned down since the pilot. Seems much more sympathetic than i'd expected, and quite a likeable character.
The scenes when they brought in the pets were really sweet, and there were a few moments in both episodes that brought a lump to the throat - much more sensitively handled than i'd feared.
I can appreciate why many don't like it, particularly those who didn't like RG too much to start with - but it's a million miles better than Life's Too Short. When I first heard about the show, I like many others probably thought it could be 30 minutes of mocking the disabled or elderly - it's good to see it's not like that. It has areas where it could improve, but it's a pretty good start in an area where it's easy to cause offence...