Yes. I'm using Olympus E-410 and find that a battery grip will be useful. Did a few research online and the feedback from most users are positive, except for one which said that there seems to be a delay hitting the shutter button and auto focus does not work. Since Olympus do not have battery grips for E-400 and E-500 series, the Ownuser battery grip looks pretty good. Apparently, it seems that it is retailed at US$109. So the offer seems good at S$79 at COMEX.
Check out their VANGUARD Alta Pro tripod too! It's an awesome offer which I am tempted to buy. If you are gonna buy, try to slash out for a bargain deal at the 11th hour before they close their booth. It is quite likely they can offer lesser than what their price tag states. I got a VANGUARD camera bag from them at a very low price last year. Good luck bargaining and happy shopping!