If it were me, I don't think I would go for the Galaxy Tab over the Nexus 7 at that price difference but here are two critical differences. The Galaxy Tab has a rear facing camera and a mirco SD card slot. If either of those are overridingly important to you then go for Galaxy Tab.
If you want the rear facing camera or the sd slot, I would wait a few weeks to see if Sammy announces a Galaxy Note 7. I have heard rumors that it should hit soon and that may be the better tablet. Hard to say though.
Check out TabletNation.com as they have a compare feature to look at tablets side by side.
You can grab the flashplayer, Samsung even offers it for the Note on their own app store. After the 4.1 update it may become a little more troublesome.