The MOTU 828s look very nice provided that you're a Mac user (as you are.) And the fact that it includes hardware pots is a nice perk over the RME hardware.
But I don't think they have nearly the sound quality as the RME/Nuendo stuff (it's the same hardware by the way. The Nuendo Multiset is simply a repackaged RME Multiface, so buy whichever you want.)
Plus, the RME hardware comes with an amazing routing mixer interface called TotalMix, which I don't believe has an equivalent on the MOTU.
I'm biased, because I'm a long time RME user and advocate. But I really do think their products are absolutely the finest you can buy. Their tech support is amazing - just post to the RME newsgroup and someone will answer you VERY soon.
Good luck,
Dennis DeSantis
http://www.dennisdesantis.com