I currently have both. For now, I feel Houdini’s code is better and there’s more to do, but Halloween has a coolness factor to it and the modes are more enjoyable for me.
I feel Houdini is one of greatest values for $ right now. A premium level machine with some listed for ~$6k or below.
Disclaimer: my Houdini is listed, but my house is full and Houdini has been in my lineup longer than any others except ‘the keepers’ that are bolted to the floor (for various reasons). I’m torn about letting it go, but I enjoy brining in ‘new to us’ games every couple of months.