Thanks for testing and passing along what worked... And you are cetainly correct - if the beacon intervals default settings are 100 - then it should work on 100. You shouldn't have to change anything. I have other devices and they don't drop.
It looks like they have some work to do on WiFi. You can pass along problems to RIM. Someone passed this link onto to me and I used it to address another problem I was having. That forum is owned by RIM. But be careful - they don't take it well over there if you aren't "thrilled silly" by every feature of your BB. BlackBerry Support Community Forums - BlackBerry Support Community Forums
Once again... thanks for passing along what worked!