The difference is that tren E has steadier serum levels. Tren a would be better for cutting in the same way it'd be better to overwhelm and kill your kidneys, your peaks are higher and your troughs are lower.
I'm wondering if write ups like this are why I still see guys in their 20s doing tren a over E and inevitably losing their shit sweating buckets unable to sleep because their levels are constantly fucked.
And you didn't mention at all that you need a daily to every other day max pinning frequency with tren a to get near the same stability as tren E has by default..