It would be extremely difficult to generate an 11 character case specific address with vanitygen, though not impossible.
edit: I tried with a bitcoin address, but not sure if it is working correctly for 2 GPUs
oclvanitygen.exe -d 0:0 -d 0:1 1BurnAddress
Difficulty: 9883693997182075238
[28.63 Mkey/s][total 486539264][Prob 0.0%][50% in 7588.9y]
Yeah, though that are GPU only. It might be way easier with Asics. I believe there were services for that too, though i did not find one yet. At least one could check how costly it would be. The ico is worth now only 0.15 bitcoins, which means the cost for creating such a vanity address must be lower than that since otherwise it would make more sense to mine properly with the hardware.
So in case this is not a correct burn address after Earlz rules then the burn address should only be safe when the cost creating it would be low. Of course i assume that the transaction and address exists. I can't check yet.
Read your thread here ->
https://bitcointalk.org/index.php?topic=1205322.0But I will answer here. My answer is similar to seedtrue's.
I have no idea how long it would take for a particular alt coin, but if it takes roughly the same time as bitcoin...
>oclvanitygen.exe -v 1MBurnAddress
Prefix difficulty: 573254251836560363813 1MBurnAddress
Difficulty: 573254251836560363813
Device: GeForce GTX 970
-snip-
Modular inverse: 13312 threads, 1024 ops each
Using OpenCL prefix matcher
[36.39 Mkey/s][total 340787200][Prob 0.0%][50% in 346208.9y]
it will take a few millenia on a GPU. Its significant faster if the M is part of the prefix.
Keep in mind that an ASIC might be faster, but there is none. An ASIC not just a fast computer its a chip that can only do one thing, but that very good/fast/efficient. Mining ASICs can mine bitcoin (or scrypt), but not generate vanity address. Its certainly possible to build one, but I doubt there is a market.