Meself I always have at least two spools for each reel I use. One spooled up with Seaguar InvisX 6 or 8 lb Flouro. The other is spooled with 20lb Spiderwire Stealth to which I add a 4 foot length of Seaguar Flourocarbon Leader material in 8 or 10lb. using a uni-to uni knot connection.
I use the Flouro for crank baits - just a little bit of stretch, great knot strength, and not so much stretch that I lose feel of the bait. I use the braid for topwater, jigging and cranking too.
For me, mono is a sorry choice for line. I hate using it after having used flouro or braid, because you have absolutely no feel for the bait, fish or bottom whatsoever. It's like fishing with a cooked spaghetti noodle. I think people like mono because it's forgiving on spinning reels, and its cheap.
Seaguar InvisX is absolutely the best flouro I've found for spinning reels, and if you have a decent reel you won't have any problems from stiff line or memory. Crappy reels tend to be less line forgiving, tend to twist line as it comes into and off of the spool.
For me it's all about feel. Really adds to the fishing fun and success. Fishing is my only hobby, I don't waste money on tee times and golf balls, so I'll glady spend a bit more on fishing line to enhance my experience.
FYI- the extra money you'll spend on these lines will be repaid by the fact that you can keep the braid on your spool for several years without it degrading due to age or sunlight.
You might break off and have to replace the flouro, but it wont' degrade in sunlight like mono either.
Monofilament line degrades with time, sunlight, temperature changes, and worst of all, it actually absorbs water and gets softer. The longer it's been wet, the more it'll stretch, the easier it will nick and break. Modern chemistry has moved beyond this 1950's technology, IMO.
Mono is dead