There is no real picture quality difference on screen between 32S310 and 32V300.
The later is suppose to have better ccfl but honestly i was not able to make out any difference.
If you did see any difference between S and V series 32 inch you must be comparing 32S200 to 32V300. 32S200 is phased out model but still many showrooms have some pieces left.
Or the 32V300 must have been in Theater mode ( which is also there in 32S310).
The biggest advantage of 32V300 is the stand, thats it. Otherwise picture quality wise they are both same.
Also when you go to showroom request a remote and reset all TV to factory settings before you start comparing
If stand is not an issue or you plan to wallmount your TV, get 32S310.