33rpm vs 45rpm - which is better

All things being equal, 45's sound better. Usually they have a much bigger gap at the end of each side where the sound deteriorates due to the angle change between the stylus and record deviating more and more from 90 degrees. May be less apparent with linear tracking arms.

Also, having more information coming through in the same time improves the depth of the sound. Usually 45's are produced with higher standards and are more expensive since 2 discs have to be used.

Vince Guaraldi - It's The Great Pumpkin, Charlie Brown: Pumpkin Shaped Vinyl (Vinyl LP) * * * (musicdirect.com)

Vince Guaraldi-Its The Great Pumpkin Charlie Brown-140 150 Gram Vinyl Record|Acoustic Sounds

The Music Direct version is 33 1/3 from the original master tapes. The Acoustic Sounds version is 45 Rpm. It says for better sound quality. 140/ 150 gram. Both are from Craft Recording. This is also from the original master tapes.

Back in the late 40's when RCA and Columbia were fighting for format ascendancy, the general consensus among those with good audio systems (my father sold them and I grew up with one in the living room) was that the 45's were the best in dynamic range especially at high frequencies.  The AES (Audio Engineering Society fellows) were really surprised that the LP won the popularity contest.