It would appear that they do still use the balls in a tumbler. You can watch the draws online, here is a link for the draw in question
In terms of the physical properties of the balls, it would only really make a difference if the same set was used each time. If they use a new set each time (or change them with reasonable frequency) then you would not be able to find patterns caused by uneven wear or the likes. I guess you might find something with manufacturing quality or perhaps the weight differences by variable amounts of printing on the surface. I’d imagine even if you were able to glean some kind of advantage from this kind of analysis it would be extremely slight and quite an expensive endeavour to try get anything out of it.