Can i make a suggestion? Do NOT strap your amps. 2 subs 2 amps run each amp to each sub and match the gains. You will most likely have better results doing this rather then strapping.
I had a guy with a pair of DD M2 amps strapped on a pair of lv4 12s. He was having bad phase issues and heating subs up fast. He brought it to me to find the problem and fix it. Simply un-strapped the amps and set the gains LOWER then previously when strapped. Instantly all issues were solved and it was 2 dB louder. I would not worry about a XL taking one of those amps daily at all, just make sure you dont push the amp into clip to "make it louder with more power". Thats how 90% of people blow stuff up, they think making it louder is as simple as turning up the volume or jacking up the amps because it still has a few more clicks. You need to do some testing to find the threshold of your system, its all about the user knowledge. The better you know your system and its limits the louder and longer you can play it.