Originally posted by Qman The DA 55-300 gets weaker IQ and slower aperture the longer you go. Lately I've not traveled with it. Instead I bring the 16-85, a longer and faster prime like a 135mm or a 200mm, and the DA14. I get fantastic image quality out of the 14mm, The extra 2mm of width, and its close-up abilities, make it genuinely useful. I'm going on a trip in June and I'm debating whether to take my A*300mm. It's compact but heavy. I won't use it often, but there will be a shot that I'll miss if I don't have it. But since it's heavy I likely wouldn't bring it all the time and I'll miss the shot anyway!
Every lens of this type gets weaker as you go longer, with the possible exception of the DA* 60-250. You use smaller and smaller portion of the front element as the lens gets longer. But that doesn't mean it's unsatisfactory.
Here's a link if you want to check out how sharp it can be.
Search: DA 55-300 PLM | Flickr
The more likely scenario is someone thinks because the lens is 55-300mm you can shoot the same way at 300mm you do at 55. 300 mm does require some skills and often a tripod. I would suggest the 55-300 is as sharp without the TC as the DA* 60-250 is with it. But it goes to 300 without a TC, so how relevant that is is a question mark.
The biggest advantage to the DA 55-300 is, it's there in theban. There's no real reason to leave it home.
I use my heavier lens when at home or near the car. Walking around... softness? What softness?
Full reach, cropped to 3840 so 1/3 has been cropped away, still razor sharp on a 55 inch TC or 4k monitor. No sense even thinking about a lens that wasn't there because it was too heavy to carry 5 km and most of my walks are at least that much. You don't define a lens by the worst image any photographer takes with it. You define it by the best you can get with it. That someone didn't achieve that is not on the lens.