I went to local music store yesterday , there are 2 heads in mint condition with the same price approx US 600,-: AMPEG SVT 2 Pro, Premier Edition and SWR SM 400S I tried and like both, the SVT has more options and versatility with the floor switch etc. but very heavy, the sound a bit ballsy. The SWR is sweeter , lighter by much and quicker response. Which one is more worthwhile? I just want to buy any one of them for collection.