The Tadao will give you more options and adjustability
Just drop the board in, put it where the old one went, you're done
Free upgrades as in, if Tadao's software ever gets updated, you don't need to pay to get the software on your board currect, just plug it in and download the stuff
Do you HAVE to upgrade ram and bolt? No. But you won't be able to make maximum use of an eframe without. Bolt is definitely the more important update, as the Outkast bolt that it uses stock is all metal, and therefore significantly heavier than you'd want.
im in UK
and i cn pick up a 07 or 08 second hand for a fairly good price, or brand new with good discount from our sponsor, so im not 100% sure. but i do really like mt cocker