Wow,
Looking at your list of guitars, I really want to learn how this new one compares to the 600, the 800, the Koa etc. Also, you have other 400 guitars, where does V-Class fit in differentiating this guitar from the others. So much to learn...
Congrats and keep on buyin’!
I will try my best to share what I know based on my current stable. Just forgive me because I am not the best at describing what my ears hear.
The 2 414's I have are not really similar in any way. The 2003 has Rosewood b/s and because it is older, it has a very unique sound. It's a lot louder than it should be for it's size (it sounds like a dread) and it has overtones for days. It is a perfect strumming guitar and does alright with flatpicking. The new 414 with ovangkol and v-class is simply amazing. It's extremely balanced and everything sounds so smooth with it. I've played every style I can think of and this guitar just makes it sound good. I'm not sure if it's overall amazingness can be attributed to the v-class or not, but it is very special for whatever reason. It also feels significantly lighter than any of my other GA's and I definitely notice in an increase in volume compared to my 614.
My 614 is such a great guitar. It is my workhorse. I am impressed by it every time I play it. It has great mids, sparkling highs, and booming lows. It adapts to whatever style I am playing. The 614 is a perfect example of how amazing Andy Powers is as a builder and designer.
My K24 is completely different than all of them. Koa has it's own sound altogether. It sounds and looks beautiful, but it is easily my least played 6-string.
The 810 is exactly what you would expect it to be, although I feel it doesn't get all the credit it should. People always talk about Martin for dreads, but the 810 can more than compete with a D-28 in my opinion.
Then there is my Rockbridge SJ. It's in a league all it's own. Brian Calhoun is amazing and he had me play for him for quite a while, asked me a ton of questions, had me play more, and asked more questions. Then he built that guitar based on the findings. When I commissioned it, I told him that I wanted him to build a guitar he thought would fit my style best. I made only a few small decisions about minor details. I just trusted his experience for that whole build and it paid off huge. I've never played a guitar that sounds as good as this one. I may love it more than kids and I want to be buried with it.
I'm not sure if any of this babble answered your question at all, but feel free to ask anything if you're wondering.