Looking at a Napoleon Propane grill (PT 450RB or PT 450RBI), and I'm trying to figure out how much of a performance difference there is if we get the 450 RBI, which has the Infrared as a main burner, or the 450 RB, where you can get the infrared as an add-on as a side burner (i.e. not in the part of the BBQ where you close the lid). Doing the add-on method is about 400 bucks cheaper, because that model doesn't come with the rotisserie (which is something i really don't see myself using all that much). Dealer (who's someone I've known for a long time) says it may be slightly cooler without the lid on (i.e. as a side burner), but i figure if i'm only using it to sear, i probably won't care if it's 1650 degrees vs. 1800. Thoughts? Suggestions?