Murray Perahia's Mozart is totally natural and true to the composer's intentions without any idiosyncracies. Mr Perahia plays Mozart with eloquence and simplicity, which allows Mozart's genius to speak for itself, something most pianists do not take care to do.
Perahia's set reminds me of an older set by Geza Anda, which also draws listeners with its simple and direct interpretation, but Perahia has an added poetic quality that gives more pleasure to the listener.
Daniel Barenboim's version (where he too directs the English Chamber Orchestra) is recommended too. It is very spontaneous playing that has plenty of vitality but purists might find the pianist over-exerting his personality a tad too much occasionally. The same can be said for Andras Schiff's version, where he is not totally comfortable to let the music speak for itself. But it is still very beautiful and sensitive playing.
After saying so much, I will still recommend the Perahia version as the definitive version for anyone wanting a complete set of Mozart piano concerti. If you care deeply for Mozart, you would want an interpretation that is simple, eloquent, but at the same time sensitive and poetically aware of the natural beauty of Mozart's beautiful way of speaking with music. In Perahia, you have all of these.