I can match the R&D target in the perfect condition and have 0.5 or so to spare (fresh option, low fuel, max fuel max, some rubber on the track at least), and is about on pace with my teammate, can't do anything with the guys in better cars really.
And the AI always run in qualifying trim in practice, i tend to ignore their times and do my own thing.
If you really want to know your real pace try out the time attack mode, if you can gold the medal you are not slow (although not alien in any means). If you are silver then you still have 1 or 2 second to gain in driving alone.
Using DRS is hugely important too, the fact that you can use it anytime in practice means my wing was opened 3 or 4 times a lap at least.