Both are equally binding if registered. You can opt one of them 

It is necessary to peruse partition deed to advice 

there may be clause in partition deed that other legal heirs relinquish their share in property 

in such a case further release deed would not be required 

You must take a decision on need base.

If the partition deed solves your purpose and if there is no objection or dispute expected from the shareholders in future, then this partition deed can remain in the same  status becasue cancellation of registered partition deed also attracts stamp duty and new registration of release deed will also attract stamp duty and registration charges 

Now there's no need to cancel partition deed and let the release deed be done on top of partition deed.

Dear client, you can opt for cancellation of the partition deed if all the parties have agreed. And after that you can make release deed. Another way is to make a sale deed and get the property from them.

- Since, the said Partition deed is registered and property got mutated on your name , it means that there is no dispute regarding the share in the property by other legal heirs. 

- Further, as per law, the consent of all co-owners required for partition deed to be valid and its execution ,hence as the said partition deed is registered it means that it was executed after taking consent of all the legal heirs , and hence there is no need of Release deed .