I would like to pick up a used G2x. I've read about how some of the early devices had lots of problems and people were returning them to T-Mobile. I'm concerned that if I pick a used one up, it'll have hardware issues and I won't be able to upgrade it to Gingerbread (or upgrading won't help with the problems). Should I be concerned or were the problems mainly software (solved by upgrading to Gingerbread)? Thanks.