Video assistant referee in football/soccer. Yes or No?

So there has been a lot of talking about adding VAR in leagues such as Premier league. VAR is currently being used in America (MLS) and Australia (A-league). What VAR or video assistant referee is going to do is look into situations like Penalties, Red cards, Yellow cards and Mistaken identity (when given a card). With this feature normal referees would not for example have the same pressure on them to give or not to give a penalty in situations where they are clueless about what happend as the VAR can review the situation and then fully see if its a penalty or not. However i do have my concerns about VAR as it can make the match last much longer and take up much time rewinding footage instead of just the referee judging the situation directly. So it has its upsides just like it has its downsides. What do you guys think about adding VAR into major leagues such as Premier league, La liga, Serie A or Ligue 1?