Various Garmin model pace accuracy--my first post!

Hello all! I've been a lurker for quite sometime and had a burning question that drove me to finally post. The issue I'm having is with pace when running, as in CURRENT pace.

I started years ago with the Garmin 310xt. I set one of my fields for what they call just "pace" and was always happy with it. Whenever I changed speed, it changed immediately. As my pace was always fluctuating by at least a second or two if not more, the pace constantly fluctuated also. I felt like it was super accurate. If I sped up from an 8 pace to a 6:30 pace, it reflected almost immediately. No rolling down, just 8 to 6:30, boom.

I later upgraded to the 910xt and had the same good current pace experience. But eventually I decided that since it was so huge on my tiny arm and since I hardly ever used 90% of its functionality that I would try a newer, simpler watch.

First tried my husband's old Forerunner 200 series. I set a field for "pace" just like I had with the other two watches. Totally different experience. First, the pace only goes in 5 second increments. The average pace of your workout is to the second, but not your current pace. Worse was the fact that as I changed pace it didn't change right away. It took so long to change sometimes that if I was going over a small hill that only took 30 seconds for example, it never fluctuated to show my slow down or my speed up. It just stayed constant as though I never went up and down that quick little hill. The worst part was that while doing my 400 meter sprints it never really caught up in that 90 or so seconds to show me if I was actually hitting my goal pace. And when it did change, it was slowly going down by 5 seconds, by 5 seconds, etc like it was rolling, when in reality I had gone from let's say an 8:30 pace to a 6:40 pace almost immediately.

So I bought the new Garmin Vivoactive thinking hey, it's brand new and must have the best accuracy Garmin has available. Not so. This watch functioned just like my husband's 200 series.

I called Garmin support and they said the best running watch they make is the Forerunner 230 and that its pace function is much more accurate than the Vivoactive. Tried it last night and it was the same darn experience as the old Forerunner and the Vivoactive. Pace only in increments of 5, didn't keep up with my pace changes.

I am about to deduce that the "current pace" technology for the 310xt and 910xt are just flat out different (i.e. better) than all the other Garmin watches. Unless someone can tell me something I'm missing??? A setting perhaps? Anyone have similar experiences?