As has been touched on it really depends on the make up/expectations of the group.
An Inn room has two proper beds (a benefit if your group has 3 or more people), you don't have to leave the main building to get back to your room ( a benefit if you have kids that are old enough to be trusted to watch the videos in reception while you relax in the Green room) if you visit the bars or restaurants and the view is likely to be better from the Inn Room.
The studio's set up (one bed one sofabed) may work better for a single or couple as it gives you more floor space and having the sofa is a nice option. While it's never possible to guarantee quiet neighbours, the studios should be quieter as you shouldn't get as much through traffic from guests walking along a corridor.
Either are a good choice, it's up to the individual (or group) as to which is the more suitable for them.