i have a spare xbox 360 that's flashed and works fine, can i go and update it and be safe online? thanks
There is no live safe solution except for an unmodded console of course. You're best to revert to stock firmware first before updating. However if you want to take the risk, you can go ahead and update.
i did all off xbl updates and can still play as long as you use a ihas you will be fine to play online.