This isn't an answer to the question you asked but it is in the ballpark I think.
I have both an E-TRAC and an F75 LTD and I had an original F75.
I would never consider choosing the LTD over the ET. If I could only keep one there would be no hard decision to make I would keep the ET. I loved the original F75 and only sold it because a friend of mine loved it soooo much, besides I have a T2. So I jumped on the LTD when it came out. My buddy has one too and he is not happy with it. He took it to the hunt at Ft. Donelson and could not use it at all, he said it was totally unstable and last year he used his original F75 with no problem (he may have a faulty unit, we are going to get together soon and compare mine with his).
So, I have not warmed up to the LTD. There has been at least one park in Atlanta where I could not use it. I used the V3 there with no problems.
Then again... I took the LTD up on the backside of Brushy Mountain and was able to use it with the small coil with the sensitivity on 99 and the disc on 0 and... it was so stable I had to wave my digger in front from time to time to be sure that it was working because it was so quiet. There are high tension lines about 100 yds from the spot and underground utilities maybe 20' from where I was hunting. I couldn't get within 10' of the utilities, I could hunt on the gravel road that the power company uses to service the high tension lines with no problem... I didn't find any relics but I did dig several old shotgun brass', so I know it was working well... could have been buttons you know.
I don't know why I have trouble in some places and in other places where I obviously should have trouble, I have none.
I need to get to a place that hasn't been pounded to death before I can form a good opinion about the LTD...
The E-TRAC on the other hand is just a marvel. It is so simple to use and picks those masked and iffy targets out like nothing i've ever seen and it is comfortable. I use it in ferrous/2 tone and it is a lot like a super stable F75 set in 2F. I rely on the conductive numbers and dig if the ferrous number is within a range that I think may be good. The "smartscreen" or crosshairs are useless on the ET since they straightened and expanded the conductive line. I also use 2 tones because it hardly falses at all in ferrous/2 tone. It is a very good machine and is easy to use. If the LTD turns out to have more depth than the ET or the V3 it will be a keeper, if not... i'll probably sell it because the ET is easier to use and it is very comfortable even though it is heavier. The V3 gives me so much information about the target, is tweakable to almost and site or target, and is just a pleasure to use.
Right now if I got an opportunity to do a limited hunt at a good site I would grab the E-TRAC with no regrets. It is fast and it is stable and, even with my bad back, I find I can swing it all day. Being able to reach down and tweak the length of the shaft is a big plus for extending your hunting time. My second choice for a relic rich site with a limited time to hunt would be a Tejon with a 5.5 HOT coil, third would be the T2, fourth would be the F75 LTD, fifth would be the SovereignGT (chest mounted in AM pinpoint) or the V3... for leisurely hunting in a park or yard I would take the ET or the V3, especially if I could hunt it again. I like to hunt sites with multiple machines and there are some sites where the Tejon will outshine all the others, (sites with lots of larger iron).
Wow, I didn't mean to ramble on like that but there it is.
Julien