It's an interesting question. My opinion is that there is a huge war between spanish festivals. In the same weekend you have BBK Live, Resurrection Fest, Cruilla Festival and Mad Cool. Besides, Download Madrid, Barcelona Rock Fest and FIB happens really close to that weekend.
In 2019, Doctor Music Festival (that was the most important spanish festival in the late 90's) will come back after a 20 years hiatus in the same location (Pirineus Zone) and I'm sure that will be the same weekend (or close to that one).
All spanish people ask the same question: why all festivals in the same dates?? The answer given by some CM of these festivals is that european routing of big artists obligate spanish festivals to happen first or second weekend in July.
So, there is a huge war between spanish fests, so huge ammounts of money are getting payed to artists.
Mad Cool is owned by Javier Arnaiz (who was one of the most important guys of LTI -BBK Live and Azkena orginzators- and by Live Nation. So some artists are booked in Europe with exclusivity by Live Nation, so it ensures that they will play Mad Cool or Download Madrid (also a LN festival).
Mad Cool and BBK have huge money grants from local authoroty in Madrid and Bilbao, so that makes them have a bit of advantage with the rest of Spanish festivals.
So, Mad Cool have: the experience of and Ex LTI chief, plus the financial support from Live Nation, plug huge grants from Ayutamiento de Madrid (local authority) and Comunidad de Madrid (autonomic authority) so now that the artist are more expensive than ever, they have more financial potencial to invest.
I don't know if this festival is profitable, but I'm sure that their promoters are risking expending a lot of money and moving to a bigger site (80k people). The festival is growing really fast, so in a few years we will realize if they can go on with it.
Madrid needed a big festival, 5 milliones people living here. I'm so happy to see it happening.
Don't be worry about security or planning. These people have been working in festivals for a long time. But this is a new festival, so it's logical that they make some mistakes that a veteran festival as Werchter or Roskilde would never make.