Hi Joe,
As per other posts, not a lot of detailed info around on running ROP/LOP on the Acclaim Type S. I was trained to pull MP back to 30.5" as you mentioned, with the prop either at max RPM or pulled back closer to 2400 RPM (supposedly matches RPM efficieny with MP). Then run ROP or LOP as preferred. I've heard the rumor about TOH at 200-400 hours too, but I have run almost exclusively LOP other than engine break-in and have almost 400 hours on the engine with zero problems. Now, I am hitting the high end of the rumored window, so we'll see what happens. I burn ~16.5 gph LOP, max CHT is 330 degrees or less, and max TIT is just over 1600 degrees. I generally see about 195 TAS between 10,000-12,000 ft That ramps up nicely as I go higher. The one thing I've found is the fuel/speed benefit of ROP vs LOP in the Acclaim S doesn't make sense to me (potential maitenance costs from ROP aside - given the unknowns). I burn an additional 4-5 gph running ROP and only gain about 7 kts running ROP vs LOP, so for me, the extra costs of fuel for a 7 kt improvement in speed is just not worth it.
The couple of things I try to be very finicky about is pulling power back gradually on descent/approach. I look for 1" of MP reduction per minute. The Acclaim will force you start thiniking in terms of time and not distance quickly. The other engine management technique is a 5 minute cool down of the turbos with the engine at idle. One question I've had about this, and have never gotten an answer I felt was a solid answer is how the temperature of the internal rotating parts of the turbo behaves relatively to TIT. I find that in the last ~2 minutes of the cooldown window, the TIT levels off. I get the concept that the internal rotating parts of the turbo can be hotter than the TIT, but my question is how does the tempture of the internal rotating parts converge with the TIT? In other words, if the TIT levels off, are the internal parts of the turbo still cooling down. I've taken it on a bit of faith that the 5 minute cooldown window is the result of some analysis of these factors, but have yet to have an explanation I feel really confident with.