With uBlock http://browserbench.org/Speedometer/ benchmark score 34. With/without Adblock Plus score - 52. It seems to uBlock may slow work of some sites.

• OS/version: Fedora 26 TwentySix/Linux 4.11.0-0.rc6
• Browser/version: Nightly 55.0a1 20170421100201
• uBlock Origin version: 1.12.1