I just downloaded 737NGX and am looking forward to a weekend of play.I'm wondering if there's a reason to buy the Extended Download Service versus just making a backup copy of the downloaded zip file or the install EXE.If my PC dies or I need to reformat, can't I just re-install it from my backup?

I burn all my addons onto CDs + the key for that AddOn. You can install from the backup from a CD or HDD.

Where does the "key" come from--during the install??

No, the key I mean is the licence number. When you buy a PMDG product you get it via E-Mail and it will be saved for you on your user account. When you run a PMDG airplane for the first time it wants to know this number to check if the plane was bought and not just stolen. I add this key to my backup on the CD to go sure I have it when I need it.

I see no reason why getting the extended D/L service.once you got the EXE Install file..... it would do the same rather it's from a CD/DVD/HDD or re downloaded from the web site.

I just downloaded 737NGX and am looking forward to a weekend of play.I'm wondering if there's a reason to buy the Extended Download Service versus just making a backup copy of the downloaded zip file or the install EXE.If my PC dies or I need to reformat, can't I just re-install it from my backup?

The advantage of the extended download does not negate the requirement to back up your installer and activation text. If you purchased the NGX on the release day or close to it, it is advantageous (IMO) to purchase the Extended Download option at time of issue of the first major update or SP so that you can download an all inclusive installer and have a year to cover for any future SPs/Updates that may be issued. This way you have one nice clean re-install process rather than using an installer and then followed by another SP/Upgrade install process. Just eliminates one chance for corruption. That is just my preference.On the other hand, if you purchase way down the road after release, all the bugs are probably ironed out out so extended download is less attractive.Regards,

----- If you purchased the NGX on the release day or close to it, it is advantageous (IMO) to purchase the Extended Download option at time of issue of the first major update or SP so that you can download an all inclusive installer and have a year to cover for any future SPs/Updates that may be issued. This way you have one nice clean re-install process rather than using an installer and then followed by another SP/Upgrade install process -----

VERY good point :)