I have the XVa and the 5x7 Wisner Plasmat set. The XVa is a much better lens, but the plasmat set performs quite well. This 8x10 set gives you 6 focal lengths instead of the 3 for the XVa and the XVa doesn't give you a short FL like the 227mm of the plasmat set. I personally think you could get 3 individual lenses like a 24cm, 280 and 360 or so and it would all be about the same for less than half the price of the plasmat set. Plus the individual lenses would be faster and probably sharper. The attraction of the plasmat set is portability, weight and this will likely be a highly collectible lens set. Look how hard it is to find an older casket set that is complete and in good condition today.
-R