Hey friend, glad to see you've produced these great educational materials about ERC404 and DN404.

However, I'd like to correct some descriptions regarding ERC404 and DN404.

The gas required for multi-transfers is substantial

Building Scattering, the one-stop marketplace for Hybrid NFTs( ERC404/DN404/SPL404)
 
https://scattering.io/

This is because ERC404 V1 only has one contract, which hybridizes ERC20 and ERC721 contracts into one. 

Consequently, third-party infrastructures like Metamask or Etherscan encounter difficulties in identifying ERC404 tokens accurately.

B) Another core issue of ERC404 is the significant increase in token IDs due to the burn/mint design. 

This means the token ID of NFTs could increase to an immense value that the contracts cannot identify as a transfer event from the ERC20 side or the NFT 721 side.

The core issues of ERC404 V1 are solved by V2 due to the excellent work from @maybectrlfreak and @0xacme.

You could find the V2 contracts here:  https://github.com/Pandora-Labs-Org/erc404/tree/main/contracts

2. DN404 solves the core issues of ERC404 V1 in the following ways:

but the contract deployment and the per unit transfer of ERC20 tokens or NFT tokens are not as significant.

1. The main issues with ERC404 V1 contract codes are:
A) One of the core issues of ERC404 is its compatibility with current token standards ERC20 and ERC721.