Still depends on the emulator. ePSXe and FPSE have noticeable lag, Retroarch is fine, Broglia's EMUs are ok, Reicast has slight lag (not noticeable unless you listen out for it). Mupen64 has noticeable lag similar to the two PS1 emulators mentioned above, N64oid is much better (I don't notice any). DraStic is fine.
That's all I can think of right now.