The only difference I've noticed with the temperature of the air out of any pipe is when smoking a short pipe with a very open draft, at which point I would describe the smoke as being "warm".
http://tobaccodays.com/2014/03/100-proven-reverse-calabash-pipes-provide-a-cooler-smoke/
Similar to the Reverse Calabash I'm sure there is a "difference" but it's not something you're going to get super excited about.
Some people might be more sensitive to smoke though, such as myself, though originally my intention was simply to get a "Gandalf Pipe" like the OP, but I'm still playing with how much of a practical difference an expansion chamber actually has on my comfort level (how sore my mouth is after smoking a bowl, I commonly have "dry mouth" from sleeping with my mouth open, the dentist says my gums are extremely sensitive and I assume that applies to all the tissues in my mouth).
http://tobaccodays.com/2014/03/100-proven-reverse-calabash-pipes-provide-a-cooler-smoke/
Similar to the Reverse Calabash I'm sure there is a "difference" but it's not something you're going to get super excited about.
Some people might be more sensitive to smoke though, such as myself, though originally my intention was simply to get a "Gandalf Pipe" like the OP, but I'm still playing with how much of a practical difference an expansion chamber actually has on my comfort level (how sore my mouth is after smoking a bowl, I commonly have "dry mouth" from sleeping with my mouth open, the dentist says my gums are extremely sensitive and I assume that applies to all the tissues in my mouth).
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