Tamron 28-300mm full frame lens. More good than bad for a one lens only travel option.
Overall the build quality is good and for the wide zoom range the lens produces sharp images. Also on the positive is the size and weight of the lens which lends itself to being a good all day carry travel lens if you only want to use a single lens.
On the negative I find the autofocus to be very slow overall and very inconsistent, especially in less than strong, bright outdoor light. I am thinking this might just be this particular lens and most other reviews of this lens do not suggest that is a problem area.
I have several other Tamron lenses (150-600mm G2, 100-400mm, and an older 18-270 Di II lens that focus much faster and more consistently than this 28-300mm. The slow focus many times requires me to manually over-ride the auto focus. This lens does allow for immediate manual focus just by turning the focus ring, so there is no need to move the switch from auto to manual first, which is a good thing. Would I recommend it, yes overall, especially if you have one that doesn't have a slow focus issue.