Rachmaninoff op 32 no 10 - una corda?

[zeljkom]

Ok, so I've been working on this gorgeous prelude for a bit and I absolutely adore it... and yet today I played it to my teacher who literally screamed at me because I used una corda in some sections (for example beginning poco piu mosso section on first page) to make sound more 'mystical', and I am sure I prefer the way it sounds than without una corda... However she just went so offensive and made me play it without una corda, so I did and she was happy... I don't know what I should think - do you guys think I should listen to my teacher and play the prelude without una corda or play it the way I like?

Thank you