I'd take a serious look at the c scope cs3mxi as well which can be purchased for slightly less than the deeptech.
This is a fantastic little detector which is simple to use but has great performance.It also runs at a higher frequency(17khz) than the deeptech which makes it slightly more sensitive to tiny silver coins like hammered farthings.There's also plenty of depth(you can do a simple mod to get a bit more),it's as light as a feather and c scopes customer service is second to none.
Don't worry about the lack of a ground balance feature either,this machine is set for our soil conditions and can be used anywhere without problems.There are some decent coil choices for the machine too making it very versatile.
These are often considered as starter machines but in reality they perform brilliantly,they don't need loads of bells and whistles,half of which are useless,to get the job done.......SIMPLY brilliant.