Bayern have a good defense, in the Bundesliga they have conceded only 13 goals in 15 matches, that is less than one goal per match. Actually, their attack is also very good, but in some matches they failed to score and this affected their result. Bayer have a long winning streak, I think that it should be interrupted soon and Dortmund is well suited for this, but I would not bet on this match, maybe only on both teams to score.
Bayern Munich performance this season in the German Bundesliga is actually a very impressive one which is why I find it ridiculous when some people say that Vincent Kompany isn't doing much at the club. The Belgian manager have really helped Bayern Munich improve in all sides compared to what we saw from them last season. Their problem this season is that they've failed to replicate their incredible performance in domestic games in the UEFA Champions League. But I believe they'll have a better second half of of the season which might see them match their record of last season in the UCL by reaching the semi finals or maybe a step further by winning the final of the competition