The Lambo in GTA would be the Infernus. Definitely in my top 10. Especially the unique orange one you get in one of Brucie's (i think) missions.
I had to look up Kaufman Cab in the gta wiki. Never remembered it. Love the classic 'cab' look of it tho. Would be nice to bring those back for V, but probably wouldn't make much sense. --- A fool and water will go the way they are diverted.