Only big downside for me, the need and the price of memory cards required for backups and purchase of dematerialized games (do not buy a 4GB is too little, choose a 16 or 32GB.)
Hint: subscribe to the service plus playstation (50 euros a year) and you will have many recent games with this subscription without paying anything more that belong to you and you will remain as a subscriber (at the moment I believe you can acquire uncharted, gravity and rush wipeout) If you also have a PS3, the subscription also allows you to download PS3 games.
For cons, I'm a little disgusted by the business practices of Sony because I missed the offer of 50 euros refunded to 5 days near and Sony wanted nothing to know is not cool to them and dishonest that kind of offer. Either we lower the price of the console is 50 euros reduction is applied with less vicious terms (50 euros paid in December, then nothing from January 1 to 21 and then returned the offer, I did not find it terrible)