I'll chuck in my 2c, I got to have a go with an sdc for the first time a few weeks back when my neighbour came around with his brand new 2300. First thing we did was swing it over my test patch that I have had in the ground for years. The sdc going flat out couldnt hit the .22 bullet that even my old qed pl1 could hear easily, I hid my disappointment in the sdc at the time.
We then went out to a small patch that I had flogged with my 4500. I put him right on the gold and set him off, 30 mins later I asked how he was going, he hadnt had a single target. He handed it to me and within 1 minute we had a small bit of gold, less than a foot away was another bit. My 4500 had missed both and so had he.
I also got out my equinox 600 and found targets that the 2300 could not hear even after they were dug up.
My point being that each machine will have pros and cons and the good users will figure it out and play to its strengths over time. Inexperience can make even the best detector look like an aldi special buy.
Currently that qed package is far cheaper than an ounce of gold, looks like good value to me.