It was a pleasure to meet the highly professional and knowledgeable Vincent Teoh who is the Editor of HDTVTest. Having been reading Vincent's review since the website started and those reviews having informed me and helped in the last two TV choices, I had no hesitation in investing in a professional calibration of my 4K 65" Panasonic AX902...and what a difference it has made! The colour balance, light output, shadow detail and depth of the image is what I always hoped for when purchasing this TV. To anyone debating whether to invest in a professional calibration...just do it. You will not regret it and based on what you will likely pay for a high performance display it is almost a no brainier. Vincent was engaging and ready to explain each step of the calibration...so aside from a thoroughly enjoyable geek out session it was also an education. Time to watch all my BluRays again :o) When I buy an OLED screen I will be straight on the phone to my new buddy. Ten out of ten. Thanks Vincent! Tony B, Hampshire