Lag: Well, it is a *STRESS* test. You know, where they try and overload the server to see where it breaks and how? What kind of fucking moron are you if you're playing a STRESS test and complaining that it's laggy? Make note of it, to be sure, but bitching and moaning about lag in a STRESS test is like crying because your poop is brown.
Character Wipes: I think it's a good idea. I think if you don't, you're opening yourself up to a lot of headaches, just from a technical standpoint. It clears up any possibly invalid or bugged items. Starts everyone on a level playing field. And, last but not least, it's a fucking beta. If you have any expectation of keeping anything you're an idiot. Short of the devs saying "Yes, xyz (being you, some people, or everyone) will be able to keep abc (character, items, whatever) guarenteed or your money back." you should expect that all "work" you put in to the game to be lost at ship. Complaining otherwise just demonstrates that you are a freeloading dick that just want to play games for free. I see that a lot. People get in to betas not to help with the quality of the game but just to have a free game. People like that can suck down razor blades and let someone who will actually give back to the game their beta codes.