May I add my personal opinion on this as found on the following:
<a href="http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=41&t=002575" target="_blank">http://www.pprune.org/cgibin/ultimatebb.cgi?ubb=get_topic&f=41&t=002575</a>
You'll see the replies in there, the same of which will probably be posted here by the moderators.
PS