Thank you for your advice!

Sounds like I'll be buying another Jumpstart or springing for a Herpstat at some point. I've been recording surface fluctuations on the surface hotspot several times today in my notebook (since he's been hiding out in the cooler hide all day) and it's gone from 90 up to 94 and back again. This isn't a huge deal I guess but any more than a 4 degree flux would be pretty bad imo. I guess the warm hide and substrate helps to keep in the heat and make the overall temp consistent but still...

Thank you also for clarification on the warm side temp vs cool side. I ordered the exo terra dual thermometer/hygrometer this week and it'll be placed on the cool side of my tank to take ambient temps.

So all together:
Jumpstart Thermostat for UTE
Jumpstart Thermostat for CHE
Zoo med thermostat w probe for hot side
Cheapo dial hygrometer that works surprisingly well so far when tested for hot side
Exo terra thermostat/hygrometer for cool side.
Fat Notebook to record temps in every day morning/night (science!)

Biggest question of mine at the mo:
I'm not sure how to secure the probe for the CHE: in the image linked on my post above it said a 'conduit to encase probe' and that 'probe should be in fixed position', but I'm not sure what it's talking about. What is a conduit and how do you encase a probe in it?

I'm currently looking at those Herpstats that have got two probes and two outlets... From the reviews I saw on the Jumpstarts, they fail pretty consistently after about 2-4 years and often in dangerous ways. (herpstat price is expensive, ouch, but I think that's what I'll end up getting eventually)