This is one of those, "you have to listen to decide for yourself" answers but if I were you, I would buy direct firing surrounds. Music doesn't seem to sound as good with dipole/bipole setups as it does with regular speakers. HT sounds almost as good with regular speakers.
I would go with direct fireing if your 50/50 I was asking myself the same question about 3 months ago and this is how I went. I ended up buying both to try out side by side and IMHO the direct sounded much better to me Im about 80 movies 20 music and I thought the dipols would sound better but I dont think they made much differance.
I do about 70% music, 30% movies, and I prefer the sound of direct radiating. Then again, 80-90% of my music listening is stereo, not multi-channel, though for multi-channel, I still prefer direct radiators.