Like the title says, is it safe to update to 3.3u (from 3.1u) via wifi? The two systems I want to update are running a Wiikey and a D2Pro. Both already have the homebrew channel installed. Will it be safe to update to 3.3u and then use the Waninkoko Downgrader to get back to 3.2u? I heard that 3.3u's only downside is that it cannot read trucha signed disks; what are trucha signed disks?