If you have CFLs* which either (1) take to long to warm up or (2) give too little light or (3) are an unpleasant colour or (4) are bent-tube shaped or sticks instead of bulb-shaped...
then I strongly recommend you buy some new ones of good quality. They have improved greatly over the last 15 years. If you want as much light as a 100W filament lamp you need at least 20W CFL. 22W and 24W CFLs are slightly brighter, if that's what's most important to you. A 12W is near enough a 60W filament lamp. Anything lower is very dim. Don't be misled by packaging that suggests a 15W CFL is equivalent to 100W. It isn't.
They last a long time, and when encrusted with dirt, dust and cobwebs, that will cut down the light output quite noticably. So keep them clean.
For lamps that are left switched on for long periods, such as porch, hall and landing, start-up time doesn't matter much. In cold conditions, such as a porch lamp in winter, they are slower to reach full brightness.
BTW a 20W CFL will run for about 50 hours for about 10p (1kWh of electricity ar current prices). For comparison, a tumble drier uses that amount of electricity in about 20 minutes. So don't imagine you are saving much money by switching them off and on all the time.
The bent-tube, or stick-shaped ones are OK in an enclosed luminaire**, but when the lamp is visible, the ones with a bulb-shaped envelope over the tubes look better. More beautiful still are the globe-shaped ones, available in 150mm (six-inch) in 25W, which I think look great. They are more expensive though.
Looking at the recent "Which tests, the Osram Duluxstar was a Best Buy that warmed up fast and had a good light output and is modestly priced (some of the other Best Buys were quite expensive, or slow to brighten)
Ikea Sparsam, GE Low Energy GLS, Philips Softone, Megaman, were very slow to brighten.
In my own house I mostly use Globes by Philips or GE, and Sainsburys value brand with the bulb-shaped envelope, which are very cheap. You are very unlikely to break the tubes in a CFL with an envelope, even if you drop it from a typical height. However I choose these for their appearance rather than their fast start-up, because I don't keep switching them on and off. Some of them are on timers or photocells. In enclosed luminaires I use the stick lamps because they are cheap and bright.
*CFL means "Compact Fluorescent Lamp" (the most common and cheap kind of energy saving lamp). "Bulbs" are what electricians plant in their gardens.
**"Luminaire" means a light fitting, or what you might call a lamp. Electricians use the term "lamp" for what you call a "bulb"