DxOMark has tested the new Tamron SP 150-600mm f/5-6.3 Di VC USD G2 lens for Canon EF mount. This lens is just released for several months ago. According to DxOMark, the score of this lens is a little lower than the old version. See the DxOMark score below:
Tamron SP 150-600mm G2 Lens Vs. Old verison lens:
Tamron has done much more than just a casual update of this lens, having totally redesigned the exterior, added improved weather sealing and a new quick-locking mechanism to maintain a set focal length, and even included a built-in Arca-Swiss compatible lens plate in the foot of the removable tripod collar.
Tamron has also refreshed the optical construction by adding an extra element to the rear. While this has resulted in a very slight drop in sharpness with respect to its predecessor (mostly in the outer zones), it’s still a great performer optically and it remains a hugely attractive option at a highly competitive price.
This post is misleading
No one buys this lens for its performance at 150mm, they buy it for its performance at 600mm
I believe at 600 mm the new version significantly outperforms the old one