I don't think there is a way to get both lipos using the DX18 telemetry. As for the Jeti, well, having gone from a DX18 to the Jeti all l can say is that if you can afford it, it is so worth the upgrade, not just for telemetry but also for things like dual redundant receivers, voice allerts, no need to use a timer (just use mAh used- far more accurate), smoother gimbals etc