I had Hella 4000s with 100W halogens, both euro beam and pencil on a previous rig. I had two of each and the euro beams were much more useful.
I now have two euro beams on my Land Cruiser with 55W 3000K HID and they outshine 35W factory HID Hella 4000s. The beam pattern is not as good as the Hella 4000 Xenon but they light up a bigger area.
The light shines as far or further than the pencil beams with 100W halogens and the light is spread over a very large area.
I have one pencil beam Hella 4000 which I have converted to the same specs as the euro beams. I just need to weld a tab to my light bar to mount it between the euro beams.
That said I would recommend getting the two euro beams.
You could also run one euro beam and one pencil if you convert them to HID. I have heard about people doing that with good results, but have not seen it for myself.
I will disconnect one of my euro beams when the pencil beam has been mounted just to check it out. Judging by the light that I get from two euros, the mixed pair should do very well.
There is one thing I miss about the halogen bulbs though. The HID throws so much light that I have to switch them off very early when someone is going to pass me or when someone is in front of me. The HID has almost limited the euro beams to off-road use only, where as with the halogens I could use the euro beams as extra high beams.