The rubber grip section wearing out is a problem for twist/grip shifters and its frustrating that it's not always easy to find spare parts at a reasonable cost. I've found that as grips become smooth they also get softer and more tacky, and I've never had any problem with hands slipping. Apart from the rubber section a twist / grip shifter is such a simple and compact mechanism it's almost impossible to break. Protruding thumb shifters are liable to be knocked and scratched on folding bikes.

I actually like that style on my beater/commuter. It doesn't need anything fancy and the pods look rather nice. Now on my toy... well I'd rather go with seperate units so I change things out at will.

However, a UCI World Cup XC race was won on Gripshifts last year.

I usually rinse sunblock off my palms with a squirt from the water bottle, then wipe 'em on my Levis.

I ride gloveless above 50 degrees and occasionally have sweat slip on my worn out SRT-600s. I bought some NOS grip replacements but they don't fit. I think they're more turn-of-the-century style, where as mine are from 1996.

I just got some 8-sp Attack Gripshifts for $40. They're all kindsa lumpy so seems like I'll be able to grab 'em while sweaty, I know they're pretty grippable in the rain.

I do have trouble with the SRT-600s in sub-25 degree weather, when I bust out the snowboard gloves. Thumbshifters rule in that situation. Haven't tried the Attacks in cold weather yet either.

Late 90s MRXs were pretty lumpy also. Better for gripping in the wet or with winter gloves.

1999 MRX:

http://farm6.staticflickr.com/5187/5...a439e912_b.jpg
DSCN1946 by Lester Of Puppets, on Flickr

Compared to ye olde 1996 SRT600:

http://farm6.staticflickr.com/5079/5...7baf0608_b.jpg

Never used triggers on a diamond frame and installed my first one on a folder, having suffered through mis-shifts with twisters over the years. Like most things, there's no pat answer.

The quality of the gear will impact the user experience, as will attention to maintenance and adjustment, and the drive system will also have a bearing as to what can or cannot be used. I now have triggers on both folders, in conjunction with SRAM derailleurs. I've found the X-7 series and above to be precise and reliable, requiring little fiddling once properly set up. The triggers are actually no larger than a short twister and take up less bar space. And as they are smaller than the brake lever, no more prone to catching on things than anything else, especially if mounted underneath.

This works for me, YMMV. My wife is as mechanically declined as they come and finds the triggers easier to use. At least she's shifting a lot more often than with the twister

I absolutely despise grip shifters. Partly because I use drop bars, but also on flat bars because they require cutting the grips, limiting your options and having two different "feels" under your hands. Also because I am also a mountain biker (drop bars on that bike too, FWIW) I feel like the purpose of the grip is for GRIPPING and nothing else. First thing I did on my Swift, before I even rode it 20 miles, was to yank off the flat bar, grip shifters and SRAM derailer, replacing them with stuff that works better for me.

Bar-end shifters solve a lot of problems, although as a mountain biker I've jabbed myself in the thighs with them too many times. On my mountain bike, my solution has been to put them on top of the bars with an IRD thumbshifter perch (which converts a bar-end shifter to act like the old thumbshifters). To me this ends up being the ideal solution for mountain biking. STI would be tempting (since I am using drops) but for mountain biking they are pretty fragile considering their cost. For flat bars I do still like trigger shifters, even though they are more complex and vulnerable than bar ends/thumbies.

I've also been using bar-end shifters on my folder. I do like their bulletproof simplicity, but I am about to convert to integrated STI shifters. On the road, I do like being able to shift without constantly moving my hands around. Despite the insane prices of most STI shifters, it doesn't have to be terribly expensive as long as you don't mind 8-speed: Shimano's ST-R500 8-speed shifter is about $130 if you buy the right lever only.