New to the forum and L Mount here. I purchased a SIGMA Bf and use the JJC aluminum grip ($40 on Amazon). While not nearly as integrated into the design as the IDS grip ($250-beautiful design integration to the SIGMA with angular geometry and matching finishes), the flat bottom of the JJC (padded with felt against the camera surfaces-essential for a metal grip IMO) is a very nice grip to hold. The rounded grip design is decent in size (could be a little slippery and small for large hands) but I think a good compromise design-wise as it is all aluminum (I have the black bf and grip), fits snugly to the camera and looks like it integrates well. It adds some heft, but a benefit in my opinion for the larger primes (I am not shooting with zooms on this one). The grip is cut out on the top to use the camera's wrist strap anchor point and also provides another looped anchor point on the the opposite right side of the camera (facing rear) to allow for the camera to hang from its side if both points used in some type of strap configuration, certainly not a professional one. I walk with the camera using a wrist strap, so this solution may not work for everyone. The "problem" with many of the other grips is that they try to incorporate a neck strap anchor point on the camera bottom. The grip then becomes bulkier in size, more difficult to pull in and out of a bag, difficult to rest flatly on it's base (with a smaller lens like a prime) and somewhat clunky looking compared to the clean lines of the camera.