The VT-100 is not at all the same as the VT-100 MKII. I've not heard the VT-100 MKIII (can't say I have read of anyone blown away by the III - generally it seems the MKII is the winner.) I had my VT-100 MKI upgraded to the II. Like a V6 to a V8!
But the real question is what is loud to you? If you really pump them up, I wonder if 100wpc is enough? FWIW, and completely ignorant of the taper on the volume pot, my VT100MKIII into 93db sensitivity/Watt/meter speakers at 9 O'Clock on knob puts out about 85db at my listening seat, in a big room, about 9 feet away. 10 o'clock would likely hit 90db with a recent (compressed and loud) CD. 90db is loud.
The diff between speaker sensitivities of 88 and 93 is not subtle. Let someone do the math.
But the real question is what is loud to you? If you really pump them up, I wonder if 100wpc is enough? FWIW, and completely ignorant of the taper on the volume pot, my VT100MKIII into 93db sensitivity/Watt/meter speakers at 9 O'Clock on knob puts out about 85db at my listening seat, in a big room, about 9 feet away. 10 o'clock would likely hit 90db with a recent (compressed and loud) CD. 90db is loud.
The diff between speaker sensitivities of 88 and 93 is not subtle. Let someone do the math.