I had a go at 25x27 on an arcsaber 10 and did the same 25x27 with bg-80 on another arcsaber 10 as comparison/control which both rackets had the same specifications. both were strung one after another.
After about 15 hours on the bg-80 power as well as the normal bg-80, i found that the former has a tad bit more power than the latter but the latter has slightly better feel and response.
and both seems to hold tension well. or at least the bg-80 power was quite alright with holding its own tension as I was used to the bg-80's characteristics.
Power/ Repulsion: BG-80 Power _ BG-80
Control: BG-80 Power _ BG-80
Feel: BG-80 _ BG-80 Power
Hitting sound: Both probably about equal with very crisp sounds coming from rightly timed shots. (BG-80 Power may be a tad bit deeper sounding compared to the BG-80's slightly high pitched sounds)
Durability: No clue yet but it is looking good at the moment for me as I've done quite a few shots which could've broken some strings in other cases but the BG-80 Power is holding its own.