Is the RA+ worth it over the RA? $50 for 256k memory is quite a bit.
I went with the RA+ to start with. That way I can include all the menus and other bells-n-whistles that I want without having to worry about memory all the time. If you read through the RA forums you will see that lack of memory is a common issue when you have more than a couple of add-ons or get too crazy with nifty features/code.
Some of what the RA users are doing now with tidal flow and weather simulation does take a bit of memory. It's worth it in my opinion.
~Charlie