Andy, I've got an 04 model spyder but don't have any noticeable flatspots at any revs. However, if you bought it, you could treat it to a DMS remap which would probably sort it out! Also, when cold, the oil pressure in mine is at 5 bar at any revs. When hot (approx 88 degrees) the oil pressure falls to about 3 bars but registers 5 bars at anything over 2000rpm. However, my sender is starting to play up and when the ignition is turned on it indicates 3-3.5 bar and 5 bar when the engine is running at any revs at any temp, so if you drive it again, have a look at the gauge when the ignition is on and when the engine is running.