In terms of soreness I get sore from every training i do although training fullbody makes the soreness easier to negotiate then training 1 bodypart a week. I cant imagine going back to squats,lunges, leg curls, good mornings/stiffies, calf raises all in the one session because it used to make my legs sore and pretty hard to walk/ take a Boris from 2 days after to 5 or even 7 days after. This in turn made going for a walk, making love, working, taking a dump and even coming back to the gym to do other bodyparts less fun for me.
Also id found when doing splitts in the past (1 day a week bodyparts) my strength increases would be random(i was less likely to find a groove, which inturn caused me to pick exercises that i shouldnt of been doing, that id never do just so i could say i did a pb.)So splitts created a false level of progression for me. Where as doing full body and practicing the same movements 2 or 3 times a week(heavy,light and moderate days) my increase in strength was/is a lot more constant. So instead of saying "yes new pb on smith machine one legged one arm rows"(like i would after splitt training) I was saying "my bench has increased by 2.5kgs every session using the same ammount of reps."