There are different orchestrations; I used to play in a ballet orchestra for six years, and I saw two, and I have heard another. There is one that has a difficult solo harp part, but another one gives most of the notes to the strings and the harp has an easy part. At the AHS Convention in San Francisco, Olga Ortenberg Rakitchenkov played the solo from the Don Quixote Pas de Deux absolutely brilliantly.
It finally dawned on me to look these up at Youtube. What an extraordinary resource on the Web this has become. Both works are there, performed by numerous ballet companies.