Both scopes are built from the Synta factory in China, the Orion 180 is almost $1300 new and the newer models have a 2" visual back but zero extras, the Skywatcher version of the same 180 scope comes with a 2" diagonal, 8X50 finder and bracket plus some kind of stock EP at $1275. The Skywatcher 150 is a smaller scope but has the same accessories as the 180 model. It used to be the Skywatcher was always more money and the Orion was cheaper cause no extras came with it but that only now applies to the Orion 150 model which is just under $700 for the bare bones OTA in which you buy what diagonal you prefer, what EP you already have and what type of finder with bracket you desire. Most people that buy the skywatcher scope already have a better diagonal, better EP's, prefer a right angle finder or red dot finder pointer instead and they sell the extras off to offset the price but in the case of the 180mm scope today the skywatcher is the better scope buy plus it looks better as far as color of the ota's go with the ends being pearly white and the ota a metal flake black but remember the bare bones ota no extras is 11.5 pounds for the 150mm and 16 pounds for a bare bones 180mm scope. Now lets place a 2" diagonal, a better visual back, some kind of finder your up around 15 pounds with the 150 and up around 20 pounds with the 180, at this point you should consider what mount your going to use.
If your Ioptron AZ mount Pro specs are right either scope should work fine. I have a 150 Orion in which its the newer model with an enlarged back opening on the OTA which Orion added back in 2017, I bought the Orion cause I already had a nice compression ring 2" visual back from TV, a WO 2" Dielectric diagonal and for most of my observing I use a WO red dot finder which works well enough. I use it on a old CG5 in which I re built it for alt/az use. I have considered to go to the 180 at times but the mount and scope now is an easy carry out for observing and placing close to 20 pounds of ota and then a larger counter weight makes moving it around a two step deal but the bigger problem is seeing in SW Florida, this is the rainy season soo when we get past October into November the skies get far better all the way till March it soo much better down here and no worries with ota cool down like in NY.