@oskarociak: If you already have it you might as well use it, it should take similar power as in the reflex but will have more output. It does benefit from a high pass filter around 35 - 40 Hz, due to the limited Xmax.
@DevFelix: Drivers like the V18-1000 are not very common and tend to be expensive as well (large voice coil and low Qts do that to any driver). The V18-1000 was basically a cheaper alternative for the PD.1850. Non- neodymium drivers like that are a b!tch to move though, you need to be in great shape to not mind.
I understand. It was clear to me that such non-neodymium drivers would make transport considerably more difficult. However, I first wanted to weigh what is possible without paying attention to the weight.
Are there drivers that deliver similarly good results, and maybe even be neodymium-loaded in the best case?
As the V18-1000 is based on the PD.1850/1, the current PD.1850/3 is probably the closest in weight and performance. The 18DS115 is neodymium and can be seen as a step up in performance but like the 18IPAL, it will need amplifiers in excess of 2000 - 3000 W per driver to really showcase their difference. Up to about 1000 - 1500 W per driver of amplifier power I would consider neodymium drivers like the LF18N401, 18NLW9400 or the 18NW100. Their Qts is a bit higher to be considered true analogs of the V18-1000 but it's still in the right ball park. While they "only" have 4" voice coils, they're of a newer generation and typically weigh less than 10 kg.