We have both in our studio, but only use the floods when absolutely necessitated by the subject. They're HOT to work around as well as really, really BRIGHT. Youu are virtually blind every time you look off set. Modelling lights on strobes are helpful, but for many years we relied more on polaroid proofs to check lighting. On digital jobs we shoot proofs directly to camera while setting up, then study them on a large monitor before accepting or adjusting an arrangement. Frankly, for much of our portrait work we already have a pretty good idea what works, based upon experience, so we can arrange lights with a minimum of fuss and proofing.