I have seen a lot of discussion on TSS about EJB's.
And I am still reluctant to implement EJB's. Performance is a tangible that I can weigh in the implementation of a real world application.I realize code reuse and standardization have there place.

 But what are some of the other major properties that make EJB's a better or worse choice to deploy as opposed to other patterns such as JDO.
 
 A succinct list of Pros and Cons with repect to applications would be very helpful.
  For instance, is the EJB security model much better for secure financial transactions ?
Are EJB's 10%, 20% or 60% slower on the average than some other patterns. When should clustering be used, considering the cost ,complexity and performance?
   I realize these assements are difficult to qualify and quantify; and there are big gray areas due to code tweaking. But some objective baslines , even fuzzy ones, would be appreciated by most developers. There seems to be a lot of energy wasted in various forms of evangelisim.