The Avalon is very overrated in my opinion. The had a reputation for a very good stereo eq and stereo compressor that used to sell for close to £4000 each. The Avalon channel cost a lot less than that and really didn't share much in common.

Pre's are disappointing when people come to spending huge amounts of money on them, in blind tests it can be impossible to tell the difference between a decent £50 a channel pre and one that costs £1,000 + a channel. The video I posted a link too above was comparing cheap mic's (they do sound different) to very expensive valve ones. The cheap set went through a cheap focusrite pre against the channels of a very expensive api desk. If the valve mic's had been put through the focusrite it really wouldn't have changed the sound much and again I doubt you could really discern the difference yet alone reliably express a preference.

Just been in a studio with expensive focusrite, Neve, pre's, worked with the band elsewhere using similar mic's through a Sony DMX 100 the pre's made no appreciable difference in the record quality.

The order of things, talent, room, mic, engineer, kit.