just for comparison, lets see how this stands up to a popular barbarian build in rage an Power attack. (well turn PA on as well)
Maldini's pure dps barbarin, quoted from his own build, FULLY kitted out does +42damage, with a +5 weapon and power attack. (disclaimer: i believe this is for his human build, dwarf will do Have different numbers with a greataxe and enhancements, warforged with their PA enhancements. He also has critical rage,
http://forums.ddo.com/showthread.php?t=115850 for reference)
barbarians get 4 attacks, making this +168 damage in a round to a single target, assuming no crits.
we have 4 normal attacks +33 (23+5PA +5 Sneak Attack) and 3 offhand attacks +27(17+5PA +5 Sneak Attack): +132 mainhand and + 81 offhand : +213 a round.
Now i know your going to say, but wait! glancing blows do a lot of damage! omgzor! yes they do, about 40 a round to nearby enemies, but remeber that free feat? since we already have power attack, go ahead and take cleave. now you will also do 1d6+33 +1d6 from whatever element you have on your weapon in an area of effect every 5 seconds. Unlike glancing blows you are also able to critical hit on cleaved attacks. This can give you a very respectable aoe power if you desire it.
------------------------------
another quick comparison: the CON damage TWF
doing 7 con damage a round + and average (assuming rapier/shortsword with improved crit) of 6/20 x4 + 4/20 x3: 36/20: 9/5, (well make it a generous 2) crits of 1d6 con DMG per round. Thats a total of 7+2d6 con DMG, average 14 con dmg a round. on a monster with 20 HD, which is INCREDIBLY generous in current content, this would deal the equivalent of +140 points of damage, bringing it short of the Barbarian and nowhere near this build while not even taking into consideration our criticals. Indeed, a monster would have to have a massive 30HD to make the typical Wounding/puncturing build on par with this build.
(fyi: this build has an average critical damage of 4/20 x 4 x 28: 22.4 mainhand + 4/20 x 3 x 22: 13.2 = +34.6 damage a round.
the barbarian assuming a non-sword of shadows(man that things imba) greatsword /w improved crit and critical rage has (4+2)/20 x 4 x 42: +50.4 damage a round)