it's in some of news articles here:
Originally posted by Michael Yuan:
There has been a lot of discussions on Qualcomm's "real intention" of supporting MIDP over BREW. BREW is an excellent provisioning framework -- they really know this stuff. But running MIDP over BREW on a small phone could have a performance impact ... I talked with Qualcomm people a couple of weeks ago. They told me that both IBM and Insignia VMs offer good performance but I have not seen any real device and other people have been saying opposite things to me. In any case, I would really like to see Verizon supporting J2ME natively ...
as far as I know performance wise BREW apps take more space than midp apps with everything else being the same..
PLus the way provisioning in brew is setup epr telecom sucks as far as the end user is concerned..so many useless hoops for a cell phopne user just to download a ringtone that they want or an app they want..