You're in good shape. No sludge there. Do always use BMW 5W-30 no matter who does the oil change. Alderson only charges about $90 for an oil change. Not a bad price for a dealership.
Then and Than are different words and they are not interchangeable.
"People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf." -- Geo. Orwell
2006 330i Sonora w/ ActiveAutoWerke flash tune :-)
2004 330i ZHP Imola/NB - missed
2000 328i TiAg - gone but not forgotten
** Join the BMW CCA www.bmwcca.org member #388003 - Use me as a referral & you could win a one day ///M Driving School!! **