Review

Not much to say. It is not some programmable profiles production grade pre-heater but it does not cost as much either. You sett it to like 150 degree for a minute then after it a minute or two at higher temperature but under the melting point and there you go. It does not have temperature probe but your multimeter does right? Bigger board? Sure why not you rarely need to heat complete board right? You just heat up under some nasty BGA and all of them are smaller then 5x5 inches( 13x13 cm) right? I think it is enough of the area so your all ground planes under the BGA are getting preheated. If your chip is particularly picky about it's profile you might need something else. Not sure how is it going to work for huge BGA chips I've just tried it with smaller and medium size chips and it worked nice. Also note that all PCB's are not created equally. Some have way more layers and huge ground and cooling planes and those will fight you way more. Remember that tools are not pulling pads and traces off the PCB impatience does it :) be sure all of the balls have reached melting point and then pull it off. Do it sooner and you will be pulling traces and pads off the board.