The Breville Barista Express Impress BES876BSS builds upon the popular foundation of the Barista Express BES870BSXL, primarily by introducing its 'Impress' puck preparation system. This enhancement significantly changes the daily user experience. While both machines feature an integrated conical burr grinder and PID temperature control for consistent brewing, the Impress model streamlines the most challenging aspects of home espresso: dosing and tamping. With automated dosing, the machine guides you to the correct amount of coffee, and the assisted tamping lever applies consistent pressure, reducing common errors like under- or over-tamping, which can ruin a shot. This makes the Impress an ideal choice for beginners or those seeking more consistent results without the manual guesswork.

A crucial, yet often misunderstood, difference lies in the pump pressure. The older Barista Express BES870BSXL features a 15-bar pump, while the Impress BES876BSS utilizes a 9-bar pump. Counter-intuitively, the 9-bar pressure of the Impress is generally considered ideal for espresso extraction, matching commercial machine standards. Higher pressures like 15-bar can lead to over-extraction and bitter shots if not perfectly managed, making the Impress's 9-bar pump a silent upgrade for actual espresso quality. Both machines employ a thermoblock heating system, which allows for quick heat-up times but can sometimes struggle with steam consistency during simultaneous brewing and steaming compared to a dual boiler system.

In terms of workflow, the Barista Express BES870BSXL offers a more traditional, hands-on approach to tamping and dosing. This grants the user full manual control, which some experienced home baristas prefer for fine-tuning their shots, although it demands more skill and practice to achieve consistency. The Impress, while simplifying puck prep, still retains a manual steam wand, allowing users to develop their milk texturing skills. The slightly larger 2L water tank and 250g bean hopper on the Impress also contribute to convenience, requiring less frequent refills.

The trade-off between the two primarily boils down to price versus convenience and consistency. For an additional $60, the Impress offers a substantial upgrade in ease of use and shot consistency, particularly for those who might otherwise be intimidated by the intricacies of espresso preparation. Both machines use a 54mm portafilter, which is smaller than the commercial standard 58mm, limiting some accessories but is a common feature in this category of home espresso machines.