A virtuosic operatic fantasy on Bellini’s famous opera, designed to show off the performer's technical and singing-tone capabilities. It relies heavily on Romantic bravura writing and florid embellishments.
Ensure the cantabile line remains projected above the dense arpeggiated accompaniments.
Comparable difficulty and character — good candidates for what to learn next.
'La Sonnambula', Fantasia Op.43 is rated Henle level 6 of 9 — advanced repertoire, roughly ABRSM grades 7–8. In the RCM system it corresponds to about level 8.
You should be comfortable at Henle level 6 — meaning you can already play level 5–6 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
A typical performance of 'La Sonnambula', Fantasia Op.43 lasts about 8 minutes.
'La Sonnambula', Fantasia Op.43 is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.
Pieces at a comparable difficulty and character include Caprice espagnol by Moritz Moszkowski, Bohemian Dance by Rudolf Friml, Allegro de Concert by Alexander Scriabin — see the full similar-pieces list on this page.