vertigo,
At CityFlyer, for ease of operation, our SOPs give a "conservative" fixed speed shedule for the RJ100 which is always 190kts min clean even at very low weights.
The only time it ever goes above 190kts is in the event of a rapid return over max landing weight, when it may increase by up to about 5kts. In this situation the last thing any crew is likely to be worrying about is saving every last drop of fuel, so I don't think you would ever hear a response of "Can we make it 194kts, please?" Taking up the time to even think about it in an unusual situation would probably not be appropriate, so you can expect the crew to just accept what speed they were given and select the correct flap setting accordingly.
To summarise then... 190kts ALWAYS works for RJ100s.
BTW, when we're high and looking for extra drag 210kts is much better than 220kts (220kts is the max speed with flap extended). It only makes a difference when we are noticably high though, and anyway, nothing's a problem for the RJ100, our 'Buccaneer style' airbrake works a treat! Whoever nicked that concept off of the Blackburn drawing board knew what they were doing.