Which time control should be used has often been discussed. Some trust on blitz or even bullet time control, others only accept games at at the classical tournament speed. I made a test and - didn't find an answer.
However, maybe my findings can give us a little hint. I used Thomas Mayer's version of epd2wb and several Winboard and UCI -engines and compared how many solutions of the Arasan 5 testsuite are found after different amounts of time.
The Arasan testsuite was choosen because it is difficult enough (at my 2 GHz AMD) to differentiate between the engines. Other testsuites are to easy (WAC for example). Most engines find almost all solutions within a very few seconds.
See this diagram of the results:
I don't have a conclusion. But maybe you are interested.
The compressed Excel sheet with all results is here:
http://www.volker-pittlik.name/winboard/times/times.zip.
Regards
Volker