I quote from the dev from Aeternity.
"Eos says they will start working on parallel execution in fall of 2018. As of now they have no plan on how parallelization will work.
This strategy is confusing to me, since their value proposition appears to be scalability through parallelization.
Parallel execution was the first problem I tackled when designing aeternity. Every other aspect of our design is shaped by our parallelization strategy. Aeternity had a working parallelized blockchain before we raised any money.
The eos code base is currently about 40 times bigger than aeternity's source code. If printed in book form, EOS would be about 4000 pages long. Aeternity would be about 100 pages. Eos is not yet functioning, they don't have a testnet. It is amazing to me that such a massive pile of software still doesn't work. This load of technical debt will make development much slower.
Adding parallel contract execution as an after-thought to such a massive code base sounds impossible to me. It would be easier to start from scratch, and include parallel execution from the beginning.
I will not be investing in EOS."
Source:
https://www.reddit.com/r/Aeternity/comments/6jiiu7/which_is_better_eos_or_aeternity/Aeternity is the better investment opportunity then EOS.