having being faced with the same decision you are many years ago. i can safely say that if you get a TM you will NOT be disappointed.
upgradeability, aftermarket support and general simplicity and reliability make the TM M14 the best bet for you money.
Get a stock TM M14, and upgrade it as you go. stay away from the G&P. Its too powerful for you if you have never played airsoft.
Lastly, DONT get an EBR.