USAG/Facom 7mm (9/32") Roller Type Stud Driver Set - popular size for BMW M50/SM52/S54 head studs.

These tools (Facom 287B Series or USAG 459/1 Series...the 2 are identical except the USAG has a knurling for better grip) are the best and most compact stud extractors I've ever used. Studs are gripped in either direction (ie, the tools can be used to remove or install studs) by 3 sets of rollers (see photo) . 1/2" drive for plenty of torque. I stock the USAG version of this tool as it's less expensive than Facom and comes with a US warranty.