I think Manchester United have a path to the final, AS Roma are dangerous as they proved against Lyon but they are beatable, Milan or Bayern Munchen will be tough but both arent on brilliant form at the moment.

everyone was beatable, united also.. AS Roma can repeat what they do vs Lyon, be an underdog and won, afterall they are now more concentrate on CL than the league because they're too far to reach the scudetto.. for Milan and Bayern they're now on-fire form tbh, Milan in 2007 was different than 2006, especially if Ronaldo was back to his oldform.. and then Bayern, they had Hargreaves back for control the midfield, and yet Makaay start to score, he's gonna be mentally back because he gets some record and that should boost him mentally.
Liverpool got the best draw, we took 4 points of them comfortably in the group stages and should knock them out, they were poor against Arsenal as well and bad finishing from Arsenal got them through, they do have threats though and shouldnt be taken lightly.
again you're underestimating other teams, PSV have been labelled 'under-dog' all the way to the quarter, but yet they got through, even for the Gunners, they are tactically strong and also they've gap in the league so they wouldnt be dizzy thinking of the league. Finishing, that's something liverpool lack also, that's why they bought strikers but yet they couldnt find someone who can score 20s regularly..
Chelsea have the toughest draw for me but should come through against Valencia CF, i can see another Chelsea vs Liverpool semi final and an all English final.
all have fair and square draw, all teams all even here, everything could happen, everyone beats decent teams, so you cant say this team get easy and that team get hard.. and probably yes Chelsea vs Liverpool semis, and i hope i don't see another Garcia's goal allowed..
Liverpool vs Manchester United final for me, that would be incredible.
yeah, it WOULD.. :p