Contrary to the other review here on Amazon I believe this disc offers an excellent survey of Walton's music, beautifully performed and recorded. Sir Charles Groves was conductor of the Royal Liverpool Philharmonic Orchestra for a number of years and EMI marked his retirement from Liverpool with a series of fine recordings in the later 1970's, including discs of music by Frank Bridge, Sir Arthur Bliss and this one, of Walton's music.
I recommend the disc very strongly and as to the question of "authenticity" over the matter of tempi, one only has to turn to Walton's own recordings of some of these pieces and compare the time taken between Groves and the composer himself. In the "Spitfire Prelude and Fugue", Groves takes 7 minutes and 19 seconds, to Walton's 7 minutes and 58 seconds. In the Prelude to "Richard III", Groves is 7.42, as against Walton's 7.32 (a mere 10 second difference), and compare these timings to Bernard Herrmann's very slow 9.48 - and Herrmann was pretty "authentic" when it came to film music. Finally, "Capriccio Burlesco" is given 6.53 by its dedicatee, Andre Kostelanetz, and the New York Philharmonic Orchestra, while Groves follows with 7.17. These timings do not support the earlier critical comments.
Look out for this disc and enjoy it.