Hi, is there any recomendation for "page size" for FB 2.0 ?

In IB6 doc I have read :
"InterBase pages are 1KB by default. A typical production InterBase
database gains 25 to 30 percent performance benefit from using a page
size of 4KB."

-Is this still true for FB2 ?
-Why is default 1K, when 4K brings better performance ?
(should be changed default in next releases of FB?)

Next:
"In general, you should use a page size larger than your largest
record, although InterBase's data compression will
generally shrink records that contain lots of string data ..."
and
"The number of records also affects the page size."

-Is there any formula, how to calculate optimal page size ?
(may it be documented?)

Next:
"If any of your indexes are more than 4 levels deep, you should
consider increasing the page size."

-In my DB I use 4K page size. More of indexes are 2 levels deep, some
1 level and only 1 index on 1 table is 3 levels deep. Is 4K page size
appropriate ?

Thanks
-Laco.