At a guess, they're less than good, especially as far as production and disposal. IIRC, they contain some mercury which isn't particularly pleasant stuff. They can't be as easy to produce as good old tungsten incandescents either. Yes, old fashioned bulbs do use more energy but since they're mainly used indoors when it's dark (and usually cool), the excess heat they chuck out won't be going to waste. Incandescents are also at their full brightness almost immediately, not an accusation that can be levelled at the fluorescents (although LEDs are better). Not sure how green LEDs are to produce either.
Much prefer the quality of incandescent lamps too! (Should point out that almost all the lights here are fluorescent, with incandescents where we need instant light [over stairs for example] or want dimmable lights.)
Yes and no
The main negative is the amount of product components and cost of disposal.
So the positive is they use less energy in use (80-90%)
The rest is negative.
The higher cost of purchase (the very cheap bulbs that appeared a couple of years back were underwritten by the energy companies as part of a government requirement. Now its subsidised insulation).
Those costs of bulb reduce the return on investment.
CFL GU10 spotlights are improving but the iriginal 7w units were very yelow now moved to a whiter light at 9/11/13 watts. Cost up to 12 x Halogen 50W units so savings are offset for longer period against cost of purchase /running costs
Failure rate of cheaper imported brands higher than expected
Disposal is costly so many go to domestic waste. So resource hungry in raw materials. To properly/legally dispose of a fluorescent tube can be more than initial purchase price. Returns Mercury and other metals. Glass tube ground up for roadfill and phosphorous recovered.
A large scale hotel group has been testing for 2 years and little commercial benefit seen in a 24 lit reception area test.
Some LED units at 7 watts to produce an equivalent 50w downlight have cost £38 bulk (cree units). Rated at 50,000 hours have failed at <250 Hours. No replacement once used.
So I am sitting on the middle ground until trial finishes in March.
For the home user I am betting similar failures have occurred in the home.
We are still at the price against reduction in cost issue
Lower wattage offset by unremitting rise in unit cost of power.
As said Plastic bags are the very tip of the icebberg.
Steve