You have the highest failure rates with outdoor temperature rated fiber SFP modules, then outdoor temp rated transceivers, then the lowest with these outdoor rated POE switches with fiber modules. Fiber transceivers mounted inside an AP have to deal with ambient temps inside the AP case at MUCH MUCH higher temps than what you find with the same fiber module in an outdoor POE or switch, so with heat being the number one killer of electronics, better to put the fiber module in the device that will be cooler. it also saves cost as those same high temp rated fiber transceivers can be thousands of dollars on their own. Usually an AP-275 with a PowerDsine solution is many thousands less than a competitor's solution where their APs cost 2-3x as much and then you add the ultra high cost temp rated fiber module, antennas, etc.
You mention the 175, you are talking about the Aruba AP-175? What does it have (outside of a DC support model) that the 27x won't? Also note that all AP-175 models are end of sale, so the only place to find them would be on the street (VARs or retailers that have stock left over). Note the 175 is also only 11n so will be orders of magnitude slower, will cost more, and will cost MUCH more to install (there is weatherization, a more complicated mounting bracket, a separate solar shield, etc). So just be aware of those caveats.
The outdoor VRD is a very good starting point.