Béla Kéler was a successful composer of light orchestral and dance music in the style of the Strauss family. This quadrille is a multi-section social dance work common in the ballrooms of 19th-century Europe.
At Henle 4 this is an intermediate piece that expects secure technique and real attention to phrasing. The main demands: precise articulation — the difference between crisp and blurred is the piece; a left hand with real melodic or rhythmic responsibility of its own; and a waltz lilt that needs charm and a flexible left hand.
Careful attention to the shifting articulations between the various sections is required.
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.
Conferenz Quadrille (Op.28) is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 6.
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 Conferenz Quadrille (Op.28) lasts about 5 minutes.
Conferenz Quadrille (Op.28) 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 Berliner Kinder, Walzer by Béla Kéler, Brigadier-Marsch by Béla Kéler, Baráti fölhívás by Béla Kéler — see the full similar-pieces list on this page.