Avamar is real crap for SQL backups it is very slow probably more slower than native backups. It is like the good old days when you were trying to backup to tapes directly. Any backup utility from companies like Redgate,Idera or quest is a good alternative even for SQL2008. The native compressed backup on SQL 2008 does the compression after the backup is complete unlike Redgate or other companies.

We use Avamar because the management brought it since it used to run for ever for large db's which are on a separate server we only use it for servers that host smaller databases.