Some people need a display screen, some don't. Without the screen you really learn to listen to the tone and can tell a good target by disc. setting and how the tone sounds when passing over the target. Bear in mind there are several things you will find that despite your disc setting will have the right conductivity and shape to give a good clean tone. Chances are these same targets will fool a display machine. I don't have displays and at present that is just my personal preference. Now that doesn't mean I won't ever try a detector with a display.
If you need the display check out the AT Pro, M6, MXT Pro, the Xterra series, Omega, T2, Fisher F series. All good detectors with different features. Personally if I were to get a display machine I would take the Xterra 505 or 705 over the AT Pro. That is just my personal opinion, others will disagree.
If you want beep and dig, Tesoro is the answer with the Outlaw, Vaquero, and Tejon. You also get a lifetime warranty.
Below is a mineralization map link where you can look up the ground mineralization for your area. Go to page 35 of 63 and look up your area for iron content.
MINERALIZATION MAP
Good luck in your decision!