I guess I have to assess each based on my age and fitness at the time and what I looked for in a bike. My number 1 favourite (Merckx MXL) was the bike that I raced when I was in my late twenties and at the peak of my fitness. I am sure that if I rode it today in my mid forties I would find it heavy and uncomfortable, but at the time, it was a beautiful riding bike and served its purpose better than anything I have ridden since.
1) Eddy Merckx MX Leader - stiff, robust, beautifully made, rode like no other
2) Colnago C40 - like floating down the road, and perfect geometry
3) Seven Axiom - my first custom bike, and despite owning several titanium bikes since, still the best
4) Cannondale CAAD5 - felt space age at the time (BB30, internal headset, oversized main tubes with slim seatstays), but it felt light, smooth and comfortable despite the aluminium tubes.
5) Moots Vamoots RSL - on paper the best bike I have ever owned, and certainly up there in the top 5, but not the very best because it lacks the fabled titanium ride comfort, but it is craftsmen built, stiff, light, comfortable and probably the bike that I will end up keeping for the longest (or until road discs come out in force)
Not many mentions of the other end of the scale in terms of the worst, but here goes. Suprisingly, some of the same brands appear at both ends of my scale, so brand loyalty is not alway a guarantee of success.
1) Specialized Allez Epic (the original aluminium and carbon glued together) - broke every one I owned (3 in one season!). Noodly, lacked stiffness and broke easily.
2) Pegoretti Responsorium (shock, gasp, blasphemy!!) - lacked the ride quality of steel, and despite a beautiful paint job, never really lived up to the hype
3) Seven Aerios (now the Axiom SLX) - triple butted, super light, but somehow didn't ride very nicely at all. Not smooth like ti, and didn't feel as light as I had hoped.
4) Pinarello Prince (aluminium/carbon version)- Pinarello's hiccup between the steel and carbon eras.
5) Specialized S Works M2 - ugly, harsh, poor geometry
I have still got every Pro Cycling and Cycle Sport magazine ever published. Always fun to look back at different eras of bikes. The late 90's/early 2000's were not a vintage era. Before that, bikes were slim, Italian, steel, sexy looking things built by craftsmen. With the end of Indurain's reign, then came the aluminium era and the early days of carbon (and sometimes a mix of the 2!), when bikes, components and kit really got hit by the ugly stick hard, until things looked up again of late post Armstrong (no reference to him BTW, just trying to reference a point in time), and todays kit will stand the test of time I think.
Just to prove my point, how many posts are there swooning over reinvented steel classics? (lots) How many posts are there swooning over modern kit? (lots) How many posts are there reminissing about late 90's bikes, early aero wheels, 9 speed etc? (none).