I've never figured out why the B125 doesn't get any respect in this country. It's a fine bar and actually more versatile than the 123. Note that the alloy and steel bars in a particular style (125 or 123) vary quite a bit in dimensions.
If you like where you are on the tops, you are better off changing bars to get the drops where you want. If your tops are a bit low as well, then perhaps change the stem as Dubbayoo suggests.
You are riding an extremely short stem to be using 123's unless your flexibility or body geometry are quite unusual. Is your frame rather big for you, necessitating the short stem? If so, you may just want to build your flexibility (hips, hamstrings mostly) so you can take the lower position. Your discomfort may be more a matter of lack of flexibility than bad position.