I was reading your post and thought , " You have got to be kidding me " !!!!!!
I am frying my poor brain trying to figure out the exact same question. ( Although I`m not a drummer )
Here is what I found out over the net , as where I live , music stores don`t like arrangers , ( I`m still trying to figure that one out !! LOL )
Here are some links to ge the basics on each A-KB: http://www.korgpa.com/pa_root/en/products/pa800_info.html?en http://www.rolandus.com/products/productdetails.aspx?ObjectId=825
The Roland has , IMO , a better sound system , but the thing is huge and weighs 50 lb`s , but how often are you going to move it anyway m so once it`s set up that becomes a non issue.
The E-80 has 2 expansion slots for added sounds ( user installable )
But it is rather dated , it has no flash drive input , although there is a USB input for midi and file transfer from computer to KB , but it has a floppy drive !
Where as the Pa800 has both host and device USB and a front mounted USB for a flash drive.
It has 22W per side and is Bi Amped , like the E80.
So as you can tell there are good points and not so good.
Both are very great arrangers , I really don`t thing you could go wrong with either one.
If you are like me , good luck , because you may be without a KB for quite some time ~~!!!! LOL
Have you had a chance to play either , if so let me know which one you like or dislike.
O__ and you can`t go wrong with Ketron either !
AJ : your needed !!
Well , best of luck to you , and welcome to the forum !!