I've had a Safari for a while, a couple Etracs, still have a Sovereign GT, an Xterra 705, and quite a number of beep-dig machines, and a Simplex. For your requirements, I would choose the Simplex over your other choices for a couple reasons.
It has 4 quick-select search modes, so you, or someone you loan the machine to, is detecting right away, instead of fiddling. It's light weight, especially compared to the others on your list, has automatic (and manual) ground balance, and completely waterproof (submerge to 10'), so no worries about getting caught in the rain, or having a machine for beaches and lakes.
Free downloadable factory updates, add features as they come out, and a couple coil choices. Built in vibrate, illuminated screen, coil spotlight for night time, wired and wireless headphone choices, and more that I'm sure I'm forgetting. The fact that it's less than half the price of the others, adds even more value. Oh, and don't let the price fool you. This is a high build quality, rugged, deep seeking machine.
. Kidding aside, never buy a lesser priced duplicate of what you have. But something opposite exactly as Greybeard said.
