I have used the Minelab 550 meter the rescaled Minelab meter to the 180 numbers, the Sun Ray DTI and the Patriot meter and even a night Hawk meter that also is a 180 numbered meter. The 180 number meters seem to give me a much better ID on those close coins with trash. The Patriot has the easiest calibration and the best light on any meter I have used, but for ID I didn't care for it as it couldn't ID the close tone or numbered targets like a 180 meter.
Those I hunt with and those around here I see get the better and deeper find all use the 180 meters of Sun Rays and I wish they still produced them as I feel they were the best there is.
The main thing is to get to know your Sovereign well as the tones is where it is at and the meter for the close tone and number ID you need to separate the trash from the coins.
Rick