100k ally points for 20 stun guns is a bad deal. Perhaps if you are in dire need and time is running out it may be an option. I open about half of that, around 50k ally points worth of bronziums and I got over 1500 shard shop currency among other things, like tons of grey, gree and blue gear, some of it I commonly have to farm. I also got 50 shards for my Jawa which brought it alot closer to 7 stars
I know watching those 20 stun guns seems very appealing but mathematically you're throwing away alot of resources. Even for 50k ally points and 10 minutes of my time I got more than 20 stun guns worth of shard shop currency and other things on top, that's half of what I'd have to pay. Now all I gotta do is wait until they show up at the shard shop and pick them up.