Hmm hard choice i've owned the Konnekt 6(Not 8 But same Family) and the Saffire Pro 24. Both have good points and bad points. The saffire has great preamps for the price range and decent ad da and comes with good software,but the latency on it is kinda high. For the Konnekt they have very good ad da it sounded very good for the price and the preamps were very good also,Big But coming lol the drivers for it were horrible. I had sample rate issues and dropout issues.
I say do your research and make the decision best for your needs,only you can do that my friend.
If TC Electronics fixed their driver problems they would have some of the best gear for the prices they sell at i think !!!