Generally speaking the LGV has the latched barrel with a heavy sleeve, a heftier stock with more added weight and I'm almost certain the piston and seal are different. Walther perfected both models over the years so there are variations on each model and not just the stocks.
I have never owned Tylorean stocked LG55 and LGV so can't make a direct comparison but the LG/V's evolved to be more refined and to "deaden" recoil by increased weight. So all things being equal, the LGV should have finer manners.
Smooth as butter.