Comparing a E-Trac to a 3300 is like comparing a Lamborghini to a Ford Pinto. However, I hunt with my buddy who has a E-Trac and he is well versed in using his machine. I have a 20 yr old White's Silver Eagle. I hold my own because I go hunt where he won't, like sidewalk parkways in front of old houses (its legal in my city...check first with your locality....it may not be). I pull the silver half dollars,seated quarters,indian heads etc because I am hunting virgin territory. In parks I go to places like the edges of sidewalks and grass/asphalt borders of parking areas (people fish keys out of pockets for automobile, even in the old days). Just think smarter........don't try to go head to head with the E-Trac. And the best for last........don't be afraid to knock on a door of a old house (without your metal detecting gear in hand), be polite and ask if you can metal detect the parkway in front of the house....if yes......complete the parkway...go back and knock on door...Thank the Person......and then ask if you can do the front yard.
If you do private property you better have developed the "Absolute Best digging recovery techniques" so as not to damage lawn. A deep (5 inch minimum, and I mean 5" minimum) three sided cut flap plug is best..make sure ya stomp flap into ground when ya put it back. Use a 14"x14" drop cloth to put the dirt on from the hole to leave no signs of digging. Research the 3 sided plug recovery technique/dropcloth technique on the Internet if your are not familiar with it. Best time of year is when grounds are moist. Don't do private property when ground is dry......any digging no matter what technique will damage grass areas. Dry season is when ya use a screwdriver to pop coins, not much depth with that technique.
Best of luck.........