What are the disadvantages (if any) of doing a Quick Format when repartitioning a drive?

You may not want to do a full format on a very large hard drive, it takes ages. a quick format serves the same purpose.

If you're worried about possible bad sectors, i recommend HD Tune for an error check, it is much faster. mind you, unlike thorough formatting, HD Tune will not mark defective sectors as bad. but if you find errors on a new hard drive you don't want to use it with marked bad sectors anyway, you will have it replaced under warranty. :)

Note: neither thorough nor quick format will wipe data on a hard disk drive beyond recovery. if that is your concern, then use DBAN.

The difference between the regular format versus the quick format is whether or not the volume is scanned for bad sectors using the chkdsk command. Both methods remove the files from the volume.

I guess you can rely somewhat on brand new HDDs to be okey, so ...

I just did a regular format on a virtual 10MB drive with Vista, and it did zero it. The quick format did not; the test data I copied onto it was still visible and recoverable. That could be either good or bad.

For a brand new drive, there is no point in zeroing it. If you want to check it for errors, there are better ways, as Molly suggests. So do the quick format.

Reasonable people may disagree as to the non-tinfoil-hat feasibility of recovering data that has been simply zeroed, as opposed to overwritten 35 times with random patterns first. Surely the latter is not worse security-wise; but the former may be sufficient, and definitely takes much less time.

With a brand new drive there are no disadvantages. Indeed, I can't recommend a normal format even for a used drive - we have Hard Drives that come close to 2TB of storage space, now. A full format would take... a long time, a quick format would take approximately 9 seconds*. Neither are secure - use DBAN for that.

*According to my testing last time I formatted a large drive (1.5TB external, about 25MB/s transfer speed), a quick format took 8 seconds, a normal format took about 25 minutes until the progress bar had a visible part (I gave up then). Not worth it!