It might not seem like much, but it can make such a difference even going to 14.25 from 14.3 or 14.5 wheelbase or vice versa, but it also comes down to concave of the boards, angle of kicks and a few other things too.
The length of the middle between the kicks (different to wheelbase) also has a fair bit to do with it, so on boards like BBS where they have different molds for different length / shape / wheelbase options, the shorter wheelbase is usually going to be a shorter board overall and would sit inside the concave of a longer wheelbase board.
DLX is the same wood and concave and has the 8.5 with a 14.25 wb which might be a good one to try just once to compare to the usual Polar 8.5 board, but that is up to you.
As was said, you can try drilling down an old board just to compare, but it will not change the point your toe flicks off the side, or more commonly off the corner of the kick, so there isn't going to be as much of a change as you might think.
As to the way a board performs, a longer wheelbase is going to be more stable at speed, turn more steadily than a shorter wheelbase on looser trucks and give you a wider stance option if you need it. You can still stand with feet closer together, but if you need the longer stance, your feet will not both be up into the kick areas. People who want or need to get lower and wider in stance will find a longer wheelbase works much better for them, more so than a shorter wheelbase board.