PSG vs Arsenal would surely be a tough one to predict. PSG barely won over Aston Villa and Arsenal surely is playing better than Aston Villa. PSG's recent league games has mostly turned into draw or loss even though they already have a large points lead.
Among Barcelona and Inter, Barcelona should easily win it as they have one of the best European team.
It is normal that both teams will play very hard as a semi-final match. The way Arsenal beat Real Madrid, you can trust them that they will do very well against PSG. And by winning the semi-final match, Arsenal can reach the final. PSG is definitely capable of playing well that is why they have reached the semi-finals where teams like Real Madrid have been eliminated. So this match will be very exciting. I was a Real Madrid fan but since they have been eliminated, I see Arsenal as the next strong team. And they have a lot of potential to win the trophy.