ok guys I was looking for a Arduino board and from looking around I think I want the Due. Im really looking for a one time buy and want something that will work with anything I through at it. that mean one with a lot of memory - I know I will want it connected to an wired Ethernet port - right now I want to build something like Billie's Hydroponic Controller LINK - I think that it will be an ambitious project for me and I dont want to run out of memory a long the way or run into slow CPU problems
I recommend an Uno for starting out as most Arduino add-ons and software works with it.
The Due only works at 3.3v - which can cause a problem with add-ons that work at 5v. Also I have not yet come close to the point where a 16Mhz Arduino is at its limits.
I am not in favour of the concept of a "one time buy" because I believe your understanding of your needs will change as you gain experience. (And, no, I don't get any financial reward if you buy multiple Arduinos )
)