Despite the stats above, this is a tough battle for the Saxons. Our results last night were 5-0 to the Vikings and 5-4 to the Saxons. The Viking preponderance in medium infantry makes a Saxon collapse very likely if their two medium infantry units can be eliminated on either side of the ridge line. In both the games all the action was on the Viking left/Saxon right, so the key seems to be getting the Saxon mediums on the left to get onto the ridge to support Aethelred on the right: then, using the hilltop position, they might have a chance. This happened in the second game (the Saxon win), but in the first the Saxons tried to fight separate battles, with catastrophic results.
The Viking battles are interesting, but beware that for this particular battle you need a second copy of the game as there are only blocks for 4 Saxon auxilia whereas you need 6 for Ashdown.