The only toilet mod I've done is remove the vinyl skirt, and now and even before then, solids have always liquified. The only liquification problem I've ever experienced is with toilet paper, and I use the Thetford brand. For a visual, see post #32 in this "Thetford Virtual Tour" thread:
http://www.trailmanorowners.com/foru...?t=8112&page=4
Of course, even if you use your toilet for urine only, if you put TP down the chute, there's a decent chance yours will look like this too, minus the tinting enhancements (at least sometimes, and if you don't backflush when dumping).
Dave