You did right by cranking up the temp towards the end, nice job. I agree , the sirloin fatty sounds great, if fact I have some room on my smoker tomorrow for one.I have an offset smoker. I actually did, inadvertently, crank up the heat toward the end. raised it about 100 degrees from 225-250 up to 350 for about 30 minutes. I wonder if that is why some of the outside was a bit crispier.
Of the two I did I think I liked the sirloin-spinach-feta one the best. The sirloin gives it a really good flavor combined with the bacon and sausage plus you can't go wrong with feta.