One of the freatures I really miss from SABnzbd though and I think would benefit NZBget would be a pre-download completion check.
Is this possible in NZBGet?
In case it's not clear what I mean here's an explination of how it works in SAB...
Pre-download check (Experimental)
If you are hit by frequent incomplete and non-repairable downloads and worry about wasted time, bandwidth or quota, there's the pre-check.
Before downloading, SABnzbd will check if enough articles are available on the server.
Currently the job will pause when the downloadable parts of the rar and par2 files together are less than 100.2% of the actual rar files.
Below that you will need to decide whether you want to take the risk of downloading something unrepairable.
Note that this an experimental feature, with the following issues:
The pre-download check takes some time, but much less than a (failed) download.
SABnzbd calculates the balance between missing articles and available par2 file. However it's not possible to make a completely accurate prediction, that's why 100.2% of the net payload should be downloadable.
The "payload" above means that the downloadable amount of RAR and PAR2 files should be at least as much as the required amount of RAR files. Anything below 100% is by definition not repairable.
Unfortunately due to weak design of the NZB format and the fact that Usenet articles and par2 repair blocks do not match, SABnzbd cannot make accurate predictions. That's why pre-check requires at least 100.2%1. Note that the average post has 110% data.
If you turn on this feature (Config->Switches), it will be used for all new jobs that enter the queue. When something in the queue is being pre-checked, the mouse-over will show "Status: Checking". Note that during this phase, the download speed shown by SABnzbd will be low (for example "7 kB/s"), and thus the ETA will be very high. You should ignore the high ETA.
When a pre-download check fails, the job will go to History with a message like "Download would not be successful, only 99.5% available "in red. You can click Retry if you want to download anyway.