Advantages and disadvantages of legacy assets

[Eric Dugas via NANOG <nanog () nanog org>]

Greetings!

Let's say you inherit legacy assets (ASN & IPv4 netblock), what are the
first advantages that come to mind (beside not having to pay annual fees).

Any disadvantages? The ones I can think of is the lack of RIR routing
security services (in the ARIN region at least). No IRR, no RPKI at all.

Eric