It really isn't such a great option because it has a huge knock-on effect on your future. You should only do a PhD if you either (a) are committed to having an academic career or (b) are in a field where there is a clear alternative career path. Doing a bit of internet stalking (sorry) I see that you have a CS PhD. That is one of the fields where there are many non-academic jobs available for PhDs. In my field, it's academia or bust, which makes the calculation of whether or not to do a PhD a very different one. If you're giving generic advice on whether or not to do a PhD, it's worth bearing in mind that CS is really the exception rather than the rule in this respect. In most fields, "do a PhD if you like doing research" is terrible, terrible life advice.