Dussek was a pioneer of the piano, and this work demonstrates the transition between the late Classical and early Romantic aesthetic. It is known for its idiomatic keyboard writing and clear melodic development within a contrapuntal framework.
At Henle 6 this is an advanced piece that assumes fluent technique and rewards mature interpretation. The main demands: independent voices that must each sing on their own line; ornaments that need to sound effortless, not squeezed in; and continuous sixteenth-note figuration that must ripple, not chatter.
Beyond that, expect precise articulation — the difference between crisp and blurred is the piece, and a left hand with real melodic or rhythmic responsibility of its own.
Maintaining a steady pulse throughout the elaborate ornamentation is the main technical hurdle.
Comparable difficulty and character — good candidates for what to learn next.
A level or two down with the same spirit — ideal if this piece is still out of reach.
Where this piece's skills lead: slightly harder works making similar technical demands.
Fantasia and Fugue (Op.55) is rated Henle level 6 of 9 — advanced repertoire, roughly ABRSM grades 7–8.
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 Fantasia and Fugue (Op.55) lasts about 7 minutes.
Fantasia and Fugue (Op.55) 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 Fantaisie by Jan Ladislav Dussek, Partita No. 1 in B-flat major by Johann Sebastian Bach, Diferencias sobre 'Guárdame las vacas' by Luys de Narváez — see the full similar-pieces list on this page.