For the last few months, I've been running Against the Giants with my group, converting to 5e on the fly. We're nearly finished G2, the big difference is I didn't reduce the numbers of any of the monsters in the modules, just straight up one-for-one conversions. It was really fun going through G1 as the players had to cook up all sorts of devious plans to get past the Great Hall, which ended in a tremendously entertaining battle. G2 has been a bit of a grind, however. The party has been using guerrilla hit-and-runs with some initial success, but the huge area of the rift makes it difficult for them to withdraw, and a group of frost giants are a lot harder to put down than a group of hill giants. So with the TftYP version now available, I'll be using it moving forward into G3.
The other thing we quickly discovered is that giants are a helluva lot more dangerous compared to previous editions. Their range attacks with boulders are hugely devastating, more so than I ever remember them being before 5e, so they are extremely deadly to fight from a distance and melee. I found such adversity brings out the best creativity in players tho, they have fared pretty well with only a 2 or 3 deaths in the series so far. Presenting each of the groups of giants as different cultures (hill giants as primitive cavemen, frost giants as ruthless Norse vikings, and the upcoming fire giants as militaristic Roman empire) has made it interesting for them, too.
My other campaign has been a 5e conversion of Dwellers of the Forbidden City - where I plan to drop Hidden Shrine of Tamoachan and the party will be entering it on our next session. I'm looking forward to it, as its one of the original classics I've never had a chance to play or run, and I'll be using the TftYP version.
