Both castles are similar, they both have a complete wall with square towers with ballista, both castles have a complete moat around the wall. One castle has more weapon buildings and is good and the other has less weapons buildings but is bad with increased production and two chapels to increase income.
from testing they are both similar in strength, bad produces more weapons and money but also loses more troops. Both snakes can compete against even saladin/wolf/etc. in 2000-10000 gold games, in 40000 games they generally lose if they are right next to a strong opponent (because they produce weapons instead of buying mercenary, and because of their smallish castles)