Surprising. You are aware of the gaps in the vocabulary, and they are annoying; but it’s a buzz when you manage to actually hold a decent conversation anyway. The last conversation I had in Klingon was the most surprising: at an airport, about how come deixis is pronounced with an [aj]. You wouldn’t think Klingon was well suited to discussing English phonetics, and it isn’t, but we managed it anyway. (My answer at the time was wrong, btw.)
I’m astonished to this day that I even managed a pun in a confrontational situation, when I first introduced myself to the Klingonists of America:
[Prominent Klingonist I had given offence to]: SaH ‘Iv? (Who cares?)
Me: jISaH jIH, naDev jIHmo’! (I’m present, because I’m here!)