Time to be totally open:
Symphony No.1 is just a Mozart-Haydnesque study with few personal touches, much like the first two piano concertos.
Symphony No.2 also. The Scherzo, however, is memorable.đ
...the first two being largely forgettable, we proceed...
Symphony No.3 is powerful, masculine, exciting. Very influential and groundbreaking. The work is patchy, however, and the Finale, even though very emotional, is not of the same (quite high) quality as the other movements.
Symphony No.4 is very refined and gentle. It is also quite pallid.
Symphony No.5 is a remarkable tour-de-force, the most compact and perfect of them all. It is overplayed, though, to the point of prostitution.
Symphony No.6 is generally very boring. There are beautiful and colourful moments (Pletnev conducts it excellently), but I start yawning halfway through.
Symphony No.7 is rhythmic and interesting. All movements yield their special charms. Unbalanced it is, however, because the fast tempi prevail greatly.
Symphony No.8 is fun. But it is a divertimento.
Symphony No.9 is the greatest and as all-embracing as Mahler. The message of the work is also sublime - hard to keep the tears from flowing in the Finale, or in the Adagio too. However, the Scherzo fails to keep my attention throughout, and the Finale is just a bit too long. The 'Turkish' variation is a bit ridiculous, it is.
The positions nos. 7 and 9 are interchangeable. And definitely the even numbers pale next to the odd ones.