Depends on what you mean with "technical". Both implement the QUIC specification for obvious reasons, but there is a fair amount of difference in how they for e

Depends on what you mean with "technical". Both implement the QUIC specification for obvious reasons, but there is a fair amount of difference in how they for example handle reordering of frames, prioritization of outgoing frames and some other details which will have a yet-to-be-determined impact on performance. Besides that - one of the implementations has unit-tests - one of the implementations is in written in a by-default memory safe programming language - one of the implementations might become available to Nginx users without having to invest extra work