For What its Worth, I just bought a copy of the 150-400 and I must say its a beautiful lens, especially the internal zoom. The image quality is Excellent, with all of the lenses I have used (7-14, 12-100, 12-200, 100-400 and the 300mm F4). My only wish was that the foot had arca swiss cuts on both sides of the foot. The reason being is I shoot a lot of bird images, especially in darker canopy conditions and I use a flash with a flash bracket like the RRS (Really Right Stuff B91 QR) which sits above the camera and then have to rotate the foot so it sits above the camera and then have to jury rig the setup to work. Then it becomes difficult to hold steady. For those interested and have the same issue, a fellow on another site stated that a Kirk LP 67 (which is actually designed for a Sony lens) works and it has the required arca swiss cuts on both sides of the foot. I purchased one from B&H and it works beautifully, I believe it was $77.00. So now I can add my Flash bracket, mount my flash and connect the flash via a cable from the flash to the hot shoe of the camera (the cable is from Vello) as Olympus (now of course OM Systems) did not make one at the time. Hope this helps anyone out there that shoots with a flash bracket. Just an FYI, I shoot with Canon R5, R7, R3 and OM Systems OM1 Mark ll, and EM 1X, my choice thus far is the OLYMPUS systems. The focus system is wonderful, it has all the bells and whistles, Pro Capture (which is excellent), image quality etc etc. Also with todays software like Topaz Photo AI, Topaz Gigapixel AI and others like DXO Pure Raw, can pretty much fix any issues like noise and now even Out of Focus images can be brought back to great images. Well thats my perspective, happy shooting out these everyone.... AND PLEASE LETS ALL GET ALONG, what is going on in the World is appalling, enjoy your life, we are here but a short time.