I buy the pk301 in the middle of January , 2011 . as everybody here , I guess , I have be watch hour and hour of Youtube video and read thousand of word in review . in order to better help and explain my opinion to you , who be consider this projector , let I tell you keypoint : - I be a University teacher , and my main use be show simple graphic and text ; - my class have 40-90 student ; - most of my class be at night ; - I do not need sound and be not expect this pico projector to fill this task . so , YES , I can use it in a BIG room with 100 student . with the desk 5 to 6 meter away from the wall I can get a pretty decent big screen so they can easily read the text and see some graphic . -lrb- wall need to be white os whiteish - it be not good on a black-green board -rrb- . some people say it can not be use in a large room and I disagree . important : light need to be COMPLETELLY OFF . I try use this during my morning class and , as expect , the lamp do not have enough lumen to make the projection visible at daylight -lrb- but i know it and it be not bad for I -rrb- . the `` fan '' sound , which a lot of people say be too loud , be not a problem for I . even in a quiet room its sound be not loud or annoying . I watch a movie in my living room and with the film 's sound I could ' t listen to the projector cooler system -lrb- no , the external speaker I hook it up be not very loud -rrb- . what else ... hum , it get hot , really hot after a 1:45 hour of class . I think it be normal and predictable . the first few time I smell `` smoke '' . it cease after the third time I use the pk though . MY ONLY WARNING be : the VGA CABLE , AFTER LESS than 2 month of LIGHT USE be DEFECTIVE . projection get pink . if I hold the cable in as specific part -lrb- next to the ferrite -rrb- it stop . I have just send a email to Optoma . let 's see how it end . I recommend this equipment , some of my co-worker buy regular projector and I see they carry heavy and elephant-like unit to they class . here in Brazil we have a popular say for this . in English it sound like : '' -lrb- the other regular-sized projector -rrb- be cannon to hit a fly '' . IMO , for class , the pk301 be dead on . do not listen to people say it have not a good resolution or it have a poor contrast . it be a PICO projector . expect what be reasonable . I can live with it when I think I can put the whole set -lrb- remote control , cable , tripod , power-supply , unit itself -rrb- in my backpack add around 1kg to my back . bad thing overview : - OBVIOUSLY : poor quality VGA CABLE . bad CONTACT NEXT to the ferrite . WAITING for OPTOMA 's answer . - remote CONTROL HAD to be BOUGHT SEPARATELLY . OMG ... - tripod have to be BOUGHT TOO . seriously , Optoma . do you really think you user would mind pay , let 's say , 15 dollar more , include on the price , for a `` full set '' include the damn remote and a tripod ? omg again ... - power supply could follow the portable mentallity , right Optoma dude ? need to be smaller , but it be not bigger than the average one . - include cable be too short and have I alrady say tha one of they be defective ? good thing that make me SMILE OVERVIEW : - extremelly light , portable and small - sport a execellent construction -lrb- at least , look like - feel sturdy ... -rrb- ; - recognize the input much faster than other unity I have ever see -lrb- Samsung , Epson , 3M and BenQ -rrb- . in 8 seconds you be ready to go ! - quiet unit ; - good resolution for its size ; - good contrast for its purpose ; - several cable include to make you start -lrb- hope no other break ... -rrb- ; - micro sd slot work pretty well , so you can really go portable , leave you notebook at home and save you smartphone 's battery ; I recommend this item . but Optoma need to work with better cable supplier ...