Re: KM or Temsah
In short, I agree with what Scoop has said.
There are differences in draws between AFs, Temsahs, and KMs. AFs are the most restrictive of the three, including the purge. Temsahs have internal gauges very similar to KM Trimetals. KMs have varying draws depending on the heart type. Every now and then there are manufacturer glitches where a heart has a smaller or larger hose/purge tube in it. KM Trimetals aren't the widest KMs but they are still wide. The KM stem tubes however are all about the same size, with the exception of the older higher end ones that had slightly thicker stem tubes.
As far as Temsahs vs KMs, if you like their styling I highly recommend one. The brass Temsahs are the most solid hookahs on the market and they are the best value from a $$/weight perspective. There were issues with sloppy soldering on the first wave of brass Temsahs that came over and from what I've seen in person I have to agree. Not all of them had issues though. The more recent brass Temsahs like the World Cup and Nugget have better soldering and I was impressed by the stems when John first showed them to me. One thing I like is that the pieces that make up the outer stem are soldered together, which is something that hasn't really been done since the older quality Syrians that can't be had anymore.
One minor thing that probably doesn't matter to most is Temsahs are like the KM Trimetals in that they are size 30 shanks but their hubs are a size 26.
If you are looking into other Temsahs like those Thameshes on HC, I'd recommend a KM or solid brass Temsah over those from what I've seen. I never understood comments that Temsahs are KM knockoffs until I saw those.