the video quality shouldnt be less …. maybe check a few things:
are you interpreting the footage correctly in AE. Right click on the footage in the project window and go “interpret footage” – make sure the field order is correct.
are you viewing the in Full quality in AE?
is Pixel Aspect Ratio Correction on in AE? If so, it will look a little pixelated…. check the manual if you’re not sure what this is
maybe as a test, do an uncompressed render out of AE and compare the two in Premiere …..
try these and if you’re still stuck post again with some more details …
good luck