I believe you will find VSM 3.5 faster than ASM/VE.  Re: Snapshot.  As long as you realize how it works, for short term it's fine.  Another trick I use, is typicaly I'm trying to recover a file, not the entire VMDK.   Bring snapshot online, add that VMDK to a different VM.  One that you can shutdown afterwards.  By adding the VMDK from the snapshot, you can see the files, then restore just the files over the network.  Then shutdown the VM so you can remove the VMDK and put the snapshot back offlne.  ESX will let you add a VMDK live, but not remove one.  That's a very quick operation compared to a 60GB copy.  
This is a two parts questions Part 1 We tested restore from smartcopy on one of our vm, that vm has a single 60GB vmdk disk, the restore of this vm took approximately 45 minutes to complete, is 45 minutes duration normal time consumption for restoring a single 60GB vm? I thought it would only take 5-10 minutes to recover.  Part 2 In a scenario where I need immediate recovery of any vm (as oppose to waiting 45 minutes for the restore to complete) I just simply bring the snapshot online and make it writable and let users access this vm while we troubleshoot the original vm, obviously that would take lass than 5 minutes to bring the snapshot online, but what are the implication of this method.
Backup scenario advice please 