In terms of quality, Dortmund is also worth watching out for, but with the mentality that Real Madrid has, it seems like it would be a big surprise if Dortmund were able to beat them in the final.
Dortmund isn't a weak team actually and they aren't even showing any form of weakness in their preparations for the champions league finals which they are preparing towards in few weeks ahead so I'm hoping to see a very exciting and interesting champions league finals as both teams are promising an interesting play in that game actually. The mentality of Real Madrid is very strong and such that I think Real Madrid will appear even more superior in the game than dortmund but then dortmund actually looks like they have a very strong mentality aswell.
Getting to this point of the league alone is even enough to keep their mind strong thats why I believe that dortmund will be able to contend Madrid well enough even if they appear inexperienced with champions league finals, they have actually come this far by putting the required efforts of which they are definitely going to desire to get more from it even if they know how challenging it can get to be actually.