I own a G27
When it's working it's a good wheel but unfortunately all G27's come out of the factory with a design flaw concerning the positional sensor wheel. Either the screws in the housing will loosen causing it to go out or worse still the wheel boss will crack or just lose traction on the shaft causing the wheel to lose centre mid race. There are home fixes for this and Logitech will replace it under warranty however it is understood that they have not changed this fault in any way and the replacement could go the same.
I personally am fuming with Logitech for ignoring this issue, it cost me a lot of money to buy as I wanted something serious that would last.
It's your choice but I guarantee you will have to return the G27 at some time in its life to Logitech and repeat this process until a resolve is found.
