Like others said, you will likely never be detained for MS'ing. I've done a lot of MS'ing and have never come close to being detained. I have experienced the following though:
1. 30 minute waits at Walmart because of the queue.
2. 30 minute wait after purchasing the MO because something went wrong with the printer or it ran out of paper.
3. Had all of my credit cards and bank accounts from Chase shut down.
4. Had VGC's that were hacked.
5. Had VGC's that were not activated
6. Been told I can't purchase MO's with VGC's
7. Been told I can't purchase VGC's with a CC.
8. Been called by CC company about my spending levels.
9. Had CC declined when purchasing over a certain amount, even though I had plenty of available credit line left.
10. Probably more that I'm not thinking of at the moment.
Once you get to a certain level of MS'ing, it becomes less of a hobby and more of a part time job. So ask yourself if you are ready to take on a part time job. If that answer is yes, start slow and ramp up your level a little each month.