Stock Control system on PDA

hi there, have a requirement for a bottle counting system for a beer factory. current situation is as follows : beer factory has 4 production lines. each line has 10 checkpoints. at present , each checkpoints has 1 staff standing there counting the bottles manually and writing on piece of paper as the bottles go by. what we want to do is to be able to give them a PDA each with an automated software for counting all the bottles i.e staff can touch screen each time for each bottle or whatever other way. the main thing is that the software will reside on the PDA and must be able to store all the information wirelessly over to a central database in a PC upstairs. Here , managers can look at realtime information re current count at each checkpoints , see if there is any discrepancies , do spot checks etc , make hourly report etc etc , some automation etc. So solution will consist of 2 parts , the clients side and the back end database/management side. Any decent PDA (windows pocketpc) with wifi will do , probably we will use the likes of HP of Palm , not sure which one is better. Let me know what you think , thanks