HTC Hero :: WiFi Really Annoying / Can Get Replacement Handset?

I know there are numerous threads on here about dodgy wifi, but I think mine is a more unusual problem then most are finding.My problem is that wifi stays connected all time when it should do, but using apps that download data are all unreliable. Nearly every time I want to download something, wether it be a webpage through browser, or rss feeds through newsrob, or just to have a look at market, it only works about 30% of the time. I have to go and switch wireless off, wait a few seconds, then switch it back on and wait again. Then I can try downloading stuff.

I know I have the same problem with at least 3 wireless routers, and nothing else has the problem with any of these routers. My old iPhone worked absolutely fine with them.For example, at home I have several computers that use wifi to connect to the internet, and they NEVER have any problems with connection. My old iPhone and my partner's iPhone NEVER has any problems with wifi. I also have tried other devices (wifi webcams, etc) at home, and all with no problems. I haven't got any special settings on my router, just the factory defaults.My Hero is the only device that has any problems. Unfortunately, I don't know anybody else with a Hero, so I can't check if it's all Heros, or just mine.I'm on a Vodafone monthly contract. What are my options? Should they replace it with another Hero?