Bear, there's absolutely nothing wrong with sticking a rubbed tri tip in the oven at 350°F for 45-60 minutes to get a 120-125°F IT. There are days I don't have the time to fire up the Kettle, and I've got a trimmed, dry rubbed TT in the fridge. I put it in a quarter sheet pan with the meat on a grate. Slice it up and eat like steak.
I've found that searing first in a skillet for 7-8 minutes a side adds a little carmelization flavor, but not a huge amount. It does cut the roasting time down a bit, but one more dish to wash.
Select Grade TTs are about all I find these days at my grocer, but they are always tender and flavorful. Untrimmed TTs were on sale last week for $3.98/lb, but my freezers were full or I'd have picked up 4-6 more.