diagnosing problem is of paramount importance... to properly diagnose engine misfire, I would recommend connecting the car to diagnostic equipment or a computer running some software... you can do at a dealer at enormous cost, or indy for some savings, or yourself at a cost of a $40 for OBD cable and BMW-specific software and an WinXP laptop...
even if the engine does not throw codes, the GT1 or INPA can monitor live engine data and you can spot rough cylinders... it can also tell you what causing the misfire, but in most cases you would not be so lucky...
when using the coils i would suggest using either the OE coild from a dealer (too expensive) or OEM coils, in this case BOSCH... the BOSCH part must be identical to the BOSCH part of the OE coil - since you don't have a signature identifying your ride, i can only speculate that you have a V8, either 4.4 or 4.8... in this case, a BOSCH part # 0221504464 should be the one... for a plug, you can go with the BOSCH or NGK - both are OE suppliers... I went with NGK Iridium Ix Spark Plug (ZFR6FIX-11) from advanced auto parts, they are about $7 a pop, with a $25 coupon it cost me about $35...
since you have the cyls 1, 2 and 7 misfiring, have you tried to swap the coils and plugs around to see if the issue will follow?
Oh... and welcome to the forum... it seems that we got several newcomers onboard in last few days, and we did not have a chance to extend our welcome...
