Hey Chrisdeme!
There are many great beginner detectors out there, but there are a few hat stick out in my mind-
Fisher F2- I own the f2 and have been very pleased with it. It has lightning fast response and recovery speed unlike the ace 150 and 250. In addition, its depth is respectable for a beginner detector, and you can always change its coil depending on the hunting site. Lastly, unlike all of the detectors on your list the f2 provides the user with target id numbers and tone id. Together, they make it very easy to identify a target and to determine whether you should dig it or not.
Teknetics Eurotek pro- This detector has recently been released by Teknetics and is designed for the tough hunting conditions found in Europe. Like the F2, the eurotek pro has a very fast recovery speed and is very easy to use. However, I think it might go a little deeper than the F2.
Tesoro compadre/silver uMax- These detectors are made by tesoro, and they back them with their unmatched lifetime warranty. both of these detectors are SUPER easy to use, very sensitive, reliable, and incredibly lightweight. They do not have a digital display like the Fisher F2 or Teknetics Eurotek Pro, but a lot of people believe that this makes people dig more targets (so you may dig a bit more trash) and therefore pass up less good targets.
No matter which one you choose I am sure that you will enjoy it!
Happy hunting,
crazy4coins