none of them are useful... someone always manages to turn them into something to do with sex or a strange fetish they seem to carry for anal with dirty tail pipes 
Not to me maybe to you but i find some of the replies helpful.
For example the turbo whissle mine has suddenly developed i have found it seems is normal.
For the misfire i have your reply about the spark plugs, also C3PO's reply about the spark plugs failed in his. Mike saying they removed those plugs from the parts list. Very useful info when mine goes in for diagnostics on Tuesday & wednesday.
I found out a couple of users have also had the alarm siren fail like mine. Then Darren lets me know hes seen 7 to 8 of them like this. So if the dealer turns round and blaims me for the failure i have a reply to them its a known issue.
All very useful info for me.