I have been trying different things for a few months regarding deads. I used to do bent rows first to warm up my back, but switched to deads first and I just do a few warm up sets. I definatly pull more weight for more reps this way. I usually only go to 315-335 if I don't do deads first. If I do them first I do work up to 365 or more for 8-10 reps. Working through an injury now so have to be carefull. I'd suggest trying them first and going as heavy as you can do strictly.
On some days I'll also thro gm's or stiff deads in if I work hams that day. Otherwise do stiff deads on leg day, (last). I keep at least 2 days between legs and back.