Eduardo Di Capua, famous for 'O sole mio', imbues this piece with a deep, vocal-style sentimentality typical of the Neapolitan song era. It is distinguished by its expressive, sighing melodic intervals.
Mastering the cantabile tone is essential, requiring careful control over the weight of the fingers.
Comparable difficulty and character — good candidates for what to learn next.
'O sentimento is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 5.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 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 'O sentimento lasts about 4 minutes.
'O sentimento 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 'E tiempe! by Eduardo Di Capua, 'A luntananza by Eduardo Di Capua, 'O sole mio by Eduardo Di Capua — see the full similar-pieces list on this page.