Research firm Kaufman Bros. is holding onto a Buy rating for Apple stock, despite Consumer Reports saying yesterday it could not endorse the iPhone 4 due to reception issues. Kaufman sees the negative rating by CR as a potential risk, but downplays it due to high demand for the phone, and supply checks showing no slowdown in terms of either build plans or demand. Apple is still struggling to keep up with production because of supply constraints, a sign that may support estimates of 7.5 million iPhones in the June quarter, and 40 million in all of 2010. Kaufman hedges
