Ặc ặc câu kết ở FM đây này
"So, should we still keep our 24mm, 35mm and 50 primes? If you have them, keep them!
Should I trade my 28-70L for the new 24-70L? That is a difficult question to answer. If you need the extra range, I'd say go for it. However optical performance is similar with both lenses, especially at the 50-70mm range. The 24-70L is optically better wide-open at the wide angle range.
The new 24-70L provides great image quality suitable to professional standards. However, if you are thinking of replacing your 28-70L or dumping your prime collection, think again. You may already have all you need."
Thôi trình cháu kém cứ luyện công cái đã, thiết bị thẩm du cháu émo có xiền chơi như cụ... he he