My late brother used to build high performance snowmobile racing engines and he had a Unisyn for setting up the carbs (mostly big Mikunis, but a bunch of others as well). Since most of those were side-draft on an angle because the engines were tilted slightly, you could swing the Unisyn tube around for any throat attitude but you still had to sit there and hold it on and/or fiddle with it to get a reading (he had added strips of really narrow tape at intervals on the tube as reference points). I was visiting once with my Speedster so I grabbed my snail meter from the car and let him play with it. He found that, even on an angle he could push it in and it would either stay in place or could be held simply with a rubber band while he made linkage/carb adjustments.
"Where'd you get this? It's great!" he said. I told him I could get another so just keep it and use it. I gave him both sized rubber snubbers to go with it, too. He picked up the Unisyn and tossed it in the trash right then and there and while it was sailing through the air towards the trash barrel I heard:
"God! That thing was a Pain in the A$$ !!!!