Over on the Gough’s Tech Zone blog, Gough has posted about his experiences in trying to obtain an E4000 RTL-SDR. He found that finding a real E4000 on ebay was tough, with most vendors claiming to have “upgraded E4000s” which were in fact R820T’s.
The E4000 tuner is becoming rare as Elonics, the manufacturer has shut down. The newer, still in production R820T tuner is in many ways better than the E4000, but the E4000 is still useful for some applications that require the higher frequencies that it can tune to.
If you want an E4000, we know for sure that Nooelec sells a Terratec version that has the E4000 chip.