I go with Marriott rewards that the Munich Marriott Hotel (Category 5) outperforms the Munich Renaissance Hotel (Category 4). Economical thinking I go with you to choose the Renaissance.
The location on the edge of Schwabing and Englischer Garten and far away from downtown is not great. The next underground station [U6 Nordfriedhof (stop for LHs airport bus) or U6 Dietlindenstraße] is a 10 minutes walk away. From U6 Dietlindenstraße you are one stop away from Münchner Freiheit and five stops from Marienplatz.
BTW.: The Oktoberfest ends at the first weekend in October (October 6th 2002), so if you would like to use your W14 voucher do not come this weekend!