I was a US Citizen for the first 51, or so years of my life, having been born and raised there. On June 21, 2013 I renounced my US Citizenship, and became stateless (without citizenship of any country).
My experience was very good. The US Embassy staff was professional, and in the case of the US Consul, friendly.
Many people who have never gone through the process often describe it as “difficult”, “complicated”, or in this question, “tricky”. It is nothing of the sort. I think as bureaucratic processes so, it is one of the most straightforward and simple!
The only information provided to the State Department is your name, address, how you came to be a US citizen and a bit of other basic info. They do not ask why you are renouncing (though you can give a verbal or written statement), they do not dig into your tax history, or your criminal history, they do not harass you over your desire to renounce.
They do read you a one page document that explains the consequences of it, and then give you a week or more to think about it.
The fee (currently $2,450) is a bit steep (at least until you look at what you are getting for it). The Embassy I renounced at accepted Visa/Mastercard.
Now, although the US State Department doesn’t dig into your tax history (nor is it relevant when renouncing), your tax situation (having tax debts, unfiled returns, significant wealth, etc) on the day you renounce may significantly affect your dealings with the IRS AFTER YOU’VE RENOUNCED!
I think the words, “complicated”, “difficult”, and “tricky” are appropriately applied to any dealings with the US Tax system. That may be especially so after you renounce when you finish up your involvement with it.
However, you’re trading that one time hassle with not having a lifetime of hassles.
To respons to a comment, I currently live in Paraguay, and I live in Paraguay as a legal resident, just the same as all the legal residents in Paraguay who have one citizenship or another.