I regularly connect at HEL, schengen to non-schengen with short connection time. I have never missed a plane and never lost baggage.

Here is a clip of me walking G20-G38 in 5 minutes. (Sorry about the quality..)
http://bambuser.com/channel/arahlen/broadcast/1581409
It is a friday evening, so very few people at the airport, but you see the distance you need to walk. The bottleneck is passport screening when leaving schengen area, especially for non-EU-citizens. If you are a EU-citizen and have a "digital" passport you can use the automated screening, with no queues at all.