Within these prices ranges (for new) my favorites are Garrett AT Pro. 7" deep dime IDed correctly, in moderate minerals & very dry ground. Amonst the best & the new Cam locks version has the problems finally corrected. STD mode very quiet & stable.
Solid air test range about 11" on dime to about 15" on nickel. ID# too small, target separation pretty good with stock DDcoil. Goes to 10' underwater for ring hunters.
8.5x11.5" DD coil. Optional concentrics 9x12, 6.5x9, 4.5. Small DD for AT Gold works.
Other favorite Teknetics G2, loud with a fairly accurate visual ID om my dime planted 5"+ deep & somewhat tilted. G2 has modulated audio so could barely hear in air test a dime at 10", 10.5" zinc, 11" quarter, 12" nickel. Not much learning involved as the number of adjustments aren't extreme. Very lightweight, can be swept fast, numerical ID is large. Separation exceptional 11" DD.
Haven't had a chance to try a White's with the newer large coils. With stock coil & 6.75x10 DD, depth was slightly above average as fas as probable coin on visual ID, but not exceptional, generally 3"-5" & rarely 6". Best wishes, George (MN)