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If you don't like Mountain Lion, you can go back to Snow Leopard at any time.
Before upgrading, I recommend you to make a backup using Carbon Copy Cloner or SuperDrive onto an external disk. With this, if you want to go back to Snow Leopard, you won't have to reinstall Snow Leopard, just restore the external disk onto the internal disk and Snow Leopard will be installed.
Also, check if your applications are supported > http://www.roaringapps.com
Not sure what you mean by update a recovery partition but if you clone a root disk with DU it will clone the recovery partition as well as the EFI partition so that the new drive is a true clone.
The drive 2 TB Seagate is a clone of my internal root drive. The EFI partition (disk2s1) the root (Mac OS Lion) and the Recovery partition (Recovery HD).
Look there are many uses for CCC and Super Drive . The ability to schedule things and to only copy changes make it a true choice for backups.
But for simple clones to make bootable drives there is nothing wrong with DU.
I'm not at all trying to discount DU; I was just curious about the ability to create a recovery HD when there is none - here is some info from CCC help:
I've found that invaluable in the cases I've had where I suddenly faced the fact that I had no recovery on my internal, which has happened a couple of times.
Actually, many moons ago when I started using CCC, I had no idea that DU could do the same thing (or maybe it couldn't at that point). I remember getting the advice to use CCC or SuperDuper here in the early days of my using a Mac.
All I see is CCC's ability to clone a recovery partition not make one from scratch. not even sure how it could even do that.
From their FAQ
Creating a new Recovery HD volume
(stuff about creating the disk partition deleted)
5. Clone a suitable Recovery HD volume from another disk (such as the startup disk) or an archive of the Recovery HD volume onto the newly-created Recovery HD volume
Anyway as I wrote above CCC has its place in the backup sphere and I don't mean to imply that DU can replace it. But for making bootable clones as the OP here needs to there is no reason to download and possibly pay for a 3rd party solution, DU can do it.
If you were on Snow Leopard, it means that you have a machine including the Snow Leopard installation DVD.
Just insert it, restart and after the tone, hit C.
The system will boot on the DVD, you will be able to reformat your disk and resinstall Snow Leopard etc ...
PAY ATTENTION : save you datas before this !! else you will loose everything ! In any case, you will lose all your personnal configurations by starting to a fresh installed system.
There is no other solution to come back from ML to SN !
If you have lost your DVD, you still can bye one on the Apple store !