In over 15 years of watching planes at Renton, I don't think I have ever seen a 727, 737, 757, or any other commercial jet land there. I do know that early in the test program a 747 landed there and came in too low resulting in a gear and right wing collpse, but that was in the early 1970s I think.
Departures out of there aren't exactly regularly scheduled either. It's more a matter of flying it out when all work on it has been completed and getting the pilots and engineers there and ready for the test flights. They usually come out of there between 9 AM and about 5 PM. I have seen days where three or four planes would take off during the day. I have also gone weeks without seeing a jetliner take off. I have seen them take off on every day of the week except Sunday so it is really a hit and miss ordeal trying to see one take off.
While drivng down along Lake Washington I have seen planes take off from Renton (always on 31) and it is quite a sight. They follow a rather steep and fast departure climbing out quickly then turning to the east usually to avoid traffic out of Sea-Tac and Boeing Field. The last one I saw, a 737-700 in SWA colors, was easily at 5000ft MSL by the time it reached Mercer Island and began a turn to the right and followed I-90 for a minute then circled to the right to head out over the Olympics where most of the test flights are done.
Compared to the normal Cessnas and other light planes out of Renton, seeing a 737 or 757 climb out is a real sight to see, you just need to get lucky when you are driving by.