Friends, Romans, Countrymen... lend me your ears! 'Cause I have a question, please.

I have a 10.5" AR pistol for HD that I have been debating making into an SBR. My reasons for wanting to do so are:
1) I'd like to put a stock on the gun, or at least shoulder the brace without issue
2) I'd like to install a vertical grip on the forend
3) I'd like to not be worried about all the ATF scorecard BS, if I take my gun to the range or a class or (God forbid) use it for it's intended purpose

So my questions are:
- What are the drawbacks of completing such a conversion (other than the $200 tax)?
- Has anyone regretted making the switch?

Thank you in advance for your comments and advice.