It really depends on you.
If you DONT want to use ADNM on a given machine, use the UNMANAGED version of avast (avast Professional or Server Edition).
If you DO want to use ADNM on a given machine, use the MANAGED version of avast (avast NetClient or NetServer Edition).
Protection-wise, the products are equivalent. The only difference is that the managed version contains the ADNM connector, and is therefore enforcing the policies defined on the management server.
Thanks
Vlk