Both ACS and Tayside are very professional. In my mind perhaps ACS has a slight edge but that is probably just because I have done more training with them. Both are great.
The weather can be an issue but not really any more so than anywhere else in the UK. Perth and Dundee are more towards the east coast of Scotland and tend not to be as bad as the western areas. During the winter the biggest difference compared to down south is probably the strength of the winds aloft, 30-40kts at 3000ft is quite common. People go out and do their IR tests in that though and for the most part do well.
Procedural NDB to RWY 09 at Dundee, with an off airport beacon and a massive tailwind, followed by a circle to land to 27. If you can do that single engine in a Seneca you can do pretty much anything instrument flying wise!
