The old "Vomit Comet" title applies to all "Wave Cutters". It stems from the fact that people who travel well on conventional ferries have always traditionally found the cat's leave them queasy! Having worked for a well known camping company this was always proven out by staff trips and customer comments. I myself am seasick on traditional ferries but not on Speedferries.
Having said that we have tried Speedferries 4 times. They were late every crossing (apparently the only guarenteed sailing on time is first of day). On three legs they ran out of water for the toilets, which was not a pleasant experience.
We are also frequent travellers on the tunnel and agree that the extra charge weekends have increased. This is OK in sumertime aswe have the light nights and an aired property, but a pain in darker nights. Yes, there can be chaos when there is a problem, but that is occasional and the ferries can be exactly the same. It is the most convenient form of travel based on comfort and speed as far as we are concerned.
The one thing I would like to see is that Eurotunnel look at geogaphical location of members in some way as being from the North West or further North we have very early and long journeys to make the cheap crossings. Being on the doorstep or within an hour or two's drive gives people a massive advantage to take all the cheap crossings!