I am new to the business, too; however, I suggest making the decision based on how attached you are to the particular piece of writing you are trying to sell.  If you look at it as a breakthrough piece that helps establish clips, either electronic or in print, then take the money and the notch on your belt.  If this is a piece that you view as your swan song, that you feel deserves much higher pay and accolades, then the decision is yours to keep tighter control over it.   This is just an opinion from another newbie, but I hope it helps. 

Also, keep in mind that if they are only asking for electronic rights, you still can sell first & subsequent serial rights in the print market -- at least this is the way I understand it from everything I've read.  Maybe someone else out there can help clarify this more for both of us!