Am I missing something obvious here, or is there an easier way to get the bloody torx yoke bolts out? I snapped a Halfords Professional T55 Torx bit yesterday, went and got it swapped at Halfords, came home (a round trip of 80 miles), put the replacement Torx bit in this morning and tried to undo the bolt again and snapped the Torx bit instantly!

That means another 80 mile round trip to go and get ANOTHER replacement. I've managed to get one bolt undone properly, another one is most of the way out and has now got pretty much stuck good and proper. On the other side, one is slightly undone and I haven't managed to shift the final one yet. I've soaked all the bolts in 3in1 penetrating oil, and my intention is to replace the bloody things with proper hex bolts when I put it all back together again.
Does anyone have any hints, tips or suggestions on how to get the bloody things out? It took me a whole day to do the rear brakes last weekend, and it's already taken me longer than that to do the front brakes, which should only take an hour or so. I'm doing this on axle stands outside the house, so please take this into account with your suggestions. I may just put the old brakes back together, if I can shift the stuck bolt, to get the car mobile and then get it into a garage for them to get the bolts removed. I don't like being outdone though!