Roman Legionaries Vs. Medieval Heavy infantry

[fasta]

If the Empire had remained it would of adopted new tec advances and would be armed as well if not better than a middle age army. But if they had remained there wouldn't of been a middle ages!

...but the Empire DID remain, and while their territory and tax base remained intact, they were armed as well as any other medieval state. Whilst there definitely was a middle ages despite this, it could be said that in the Eastern Roman Empire there was no Dark Ages.

This is one of reasons these type of questions help no one. This is a large space of time when lots of things changed.So it would of helped the question to add dates.

When you say to use your quote "the Empire DID remain" we are talking of the Eastern part?But "their territory and tax base remained intact" only for a short period.

It is true that part of the Eastern Empire did remain and became more influenced by the East in weapons,armour and troop types(which had beening going on for a while)but they were still part of the middle ages if we are running with the question.We tend to see things from a Western(normal thing that happens)but time rolls on for the whole world.
The East had their own "Dark Ages"with the reduction of land because of the raise of new faiths etc.

But let me say that having fought troops from the 1400's from the position of Roman infantry from the 400's last year we had the edge and left the field pretty much intact.