Olympus has added to their professional lens line-up with a 300mm Micro Four Thirds pro lens, replacing the need for the heavier, slower, Four Thirds 300mm F/2.8. The new lens (MSRP expected around $2,500 USD) has already been reviewed by SLR Gear with exceptional performance and some details about the new (especially for Olympus) in-lens image stabilization system. In the past, Olympus has relied on in-camera stabilization, and using an IS lens (such as those from Panasonic) required making a decision as to whether the combination would use the body's or lens' IS system. With compatible cameras, such as an OM-D E-M1 with updated firmware, the new 300mm f/4 IS Pro ED M.Zuiko Digital lens can function in conjunction with the body's IS, providing 6-stops worth of stabilization. SLR Gear's reports also report issues with shutter-shock, although bodies that provide an electronic shutter (such as the aforementioned E-M1 with its silent mode) can eliminate that problem.