I would consider that more of a stiff leg deadlift.
Are you keeping your back neutral ? if so most people dont have the flexibility to go that much further down on them. I dont do RDLs all that much, but when I do them I usually find myself doing them do a bit below my knee and really feeling the stretch. Unfortunatley my back fatigues a fair amount before my hamstrings (although, the NEXT day, my hamstrings are real sore) mind you last time i did rdls i think it was 405 x 20.
There was a pretty good article on t-rag a little while ago by mike robertson i think on 'the perfect rdl' and it was great. Cant find it actually.. but here it is on another forum:
Perfect Romanian Deadlift