Be patient for Mars, not as large late next year 2007 Dec 18th... tho 15.9 seconds diameter, large enough for some major details even in modest scopes...

Start viewing prior as well as after Maximum, example last observation on Mars the SPC Southern Polar Cap visible few months prior to Max size, and lost due to the Martian Summer......

Was able to identify the largest feature Syrtis Major down to 9.5 Seconds Diameter in the XT8, better at plus 12.....

Frequent observation used was 250X with the XT8, the 10 inch Dob might be perhaps 300X, but skys will determine the allowed max powers....

Last weather is unpredictable, and best views may occur for a given area before and after maximum, rare are the Steady Skys, lots of viewing is eventually rewarded with nice details....

Detailed info on Mars:

THE 2007 APHELIC APPARITION OF MARS