In case its useful to anyone, I just took some more 'air temp' readings below the load, with a 0.2 in the bowl. K type probe digital thermometer.
All readings taken at a controller setting of 560f (just cos it seems to be my 'choke' cut off point atm to stop any lung complaints after hitting the SH all day, most days), by shoving the probe through the handle hole and sealing around it with silicon, me holding it in place.
Taken my choice of controller temp, I find my readings interesting. These readings are obviously affected by glass, and amount of water, and personal lungs, etc etc etc!
I was trying to top the temp out at all times. Needed a break tho!
I'll probably check these findings again tomorrow, see how much variation there is to these readings.:
Uncapped - fast draw, starts around 270f, tops out about 300f. A moderate to slow draw I managed to get up to around 400f.
Capped - fast draw, started around 400, topped out around 420. Slow draw, 370f to 400f, I was inhaling for quite a while to get the slow draw to top out tho, ran out of breath in the end.