Looking forward to trying these out a bit later, my only concern is that this would indicate that they are looking to move the 171/2 to primarily single deck operation, when there a number of services particularly in the morning that really require a double decker, I regularly use the 7.35 171 service and single deckers are usually full and standing for much of that service...
For the rest of the day though, easily the biggest upgrade I've seen to any route in the Thames Valley, surpassing even the 194 upgrade (the "new" buses for that route still didn't even have WiFi last time I travelled on them

)