bennyboy01 wrote: how does it affect Clixsense account if you try to join other PTC sites?
You are free to join other programs.
bennyboy01 wrote: should you need to use different usernames?
Not necessary but its up to you
bennyboy01 wrote: does some offers or links not work/pay if you did them on another PTC site?
If any other PTC has the same offerwall, you might find the same offer there. But some offerwalls have a limit on the number of times you can complete an offer. So if you've completed an offer from an offerwall on another site and you attempt to complete the same offer on ClixSense again, you might not get paid.
bennyboy01 wrote: are the offers any different on other PTC sites?
You will have to check that out yourself.