I have never used a smartboard myself, however:

• I attended a lecture where the lecturer used a touchscreen and his writing got projected using a “normal” (not short-distance) video projector. He used “Microsoft OneNote”. It was horrible, he had always trouble when trying to correct things, often he had to rewrite his words because of small mistakes, or he triggered undesirable “features” of the software. I would even prefer overhead projectors using foils.
• In another lecture the lecturer had to use (other rooms were not available because of repairs) pen and paper and there was a camera recording the writing (and the hands of the lecturer), then it got redirected to a video projector. There was really embarrasing, since there was not enough space and I do not see any benefits compared to blackboards.

Regarding smartboards I only have second-hand information: There is not enough space and the detection of the writing is very slow and inaccurate. It is hard to correct your writing because of the inaccuracy, thus you often have to start over with your word.

I definitely prefer blackboards—if you have an arrangement of nine blackboards you have enough room for everything you need. You can easily correct what you have written. You are flexible, you can even use colours. If you need some material you do not want to write live (or some graphics etc.) you can additionally use a video projector (or sometimes an overhead projector might be sufficient). Whiteboards are also fine, it might be a bit more comfortable to write at them, but I prefer blackboards, but that is probably a matter of taste.

I have never used a smartboard myself, however:

• I attended a lecture where the lecturer used a touchscreen and his writing got projected using a “normal” (not short-distance) video projector. He used “Microsoft OneNote”. It was horrible, he had always trouble when trying to correct things, often he had to rewrite his words because of small mistakes, or he triggered undesirable “features” of the software. I would even prefer overhead projectors using foils.
• In another lecture the lecturer had to use (other rooms were not available because of repairs) pen and paper and there was a camera recording the writing (and the hands of the lecturer), then it got redirected to a video projector. There was really embarrasing, since there was not enough space and I do not see any benefits compared to blackboards.

Regarding smartboards I only have second-hand information: There is not enough space and the detection of the writing is very slow and inaccurate. It is hard to correct your writing because of the inaccuracy, thus you often have to start over with your word.

I definitely prefer blackboards—if you have an arrangement of nine blackboards you have enough room for everything you need. You can easily correct what you have written. You are flexible, you can even use colours. If you need some material you do not want to write live (or some graphics etc.) you can additionally use a video projector (or sometimes an overhead projector might be sufficient). Whiteboards are also fine, it might be a bit more comfortable to write on them, but I prefer blackboards, but that is probably a matter of taste.