I bit the bullet and got the x tank and then some 1.8 coils. The 1.5 coils do seem a bit lackluster, but these 1.8's are really nice so far. Only been using it for about an hour, but it feels just like an upgraded version of the BVC's finally, which is what I was hoping for. The flavor seemed sort of odd on the 1.5, but seems much improved on these.
To compare, I'm using the same juice in both the Triton Mini, with 1.8 bvc, and the x with 1.8 each at 13 watts. The x seems noticeably better on flavor, but also just different. It has that same effect a bit that the 1.5 does, where it just makes flavor different. But I think it's just better overall now with this coil. No gurgling at all so far, and it's quieter than the 1.5 coil too. Just nice a smooth. I'm pretty happy so far, but we'll see how long these coils last. That'll be the big thing.
Only downside, the drip tip is still a tad bit warm when chain vaping, but not nearly as much as on the 1.5. I kinda like it actually since it gives me that cig feeling. I'm tempted to get the 4 mil extender though, which would fix it.