ive owned klipsch horns & i ran them with tubes & solid state,i prefered solid state any day over tubes,you hear all the time about how loud 5 or 10 watts will be with 104 db speakers,not 100% true,that statement is subjective to what each person thinks is loud & i will gaurentee you that 10 watts or even 30 or 40 watts will not even come close to giving you the listening level you described in your post.
the thing about khorns or any other 104 db efficient speaker is that they easily expose any weakness in the gear driving them & the biggest weakness of tube amps is the lack of a good strong bass & at loud listening levels the bass will become very loose & weak,allmost strained,from my experience people who like seriously loud music also prefer a good strong thumping bass & with tubes you wont get it.
try not to get too caught up in the whole plastic vs metal horn deal either,ive had all the horn types including the original wood type horns & at the listening levels you described none will make a difference.
klipschfan's suggestion is the best ive seen for what your looking for,try to stay away from midfi gear such as adcom,rotel,parasound ect & stay with top end gear,my personal favorite was the krell ksa 150 class a,that combo was like thunder & the khorns absulutely loved 150 wpc class a amplification.
mike.