Both systems have evolved to the point where they work very well and have similar weight, durabilty, and price. It really comes down to what you prefer. Test ride some bikes and try both of them. Make your decision based on the one that you are more comfortable with.
Some rear Grip shifters are made to work with Shimano derailleurs. Those that are work every bit as good as rapidfire does. But you do have to be careful as most of the newer Grip Shift is made to only work with a SRAM rear derailleur. The front Grip Shift works equally well with Shimano or SRAM front derailleurs.
For McTavish my point is moot, as any new bike won't come with a Grip Shift/Shimano combo that doesn't work. Again, I say try both and buy what you like to shift.
Well to the guy posting the original thread, It is totally up to you. Try bikes that have each system and see which you feel more comfortable with. My opinion is that rapid fire is better but I probably feel that way because I have been using it for ages.
From Sarasota, FL sitting in front of a computer spewing random thoughts!
Intense Uzzi SL, Masi Speciale, Trek 3700 Nashbar Single Speed, Old Cilo Road frame
Get a grip
Like everyone has said, go with what you like. When grip shift first came out I test rode a new Cannondale at my LBS and jumped a small curb, shifted in mid-air and almost killed myself and swore I'd never use them. A couple years ago I got a great deal on a Gary Fisher that had the ESP 9.0 system on it. Once I got use to using the grip shift I realized I liked it better, and now I wouldn't go back to rapidfire. My wife on the other hand hates grip shifts. So it truly is a matter of preference and in my case cost. I think you'd get used to either option and since the quality is almost equal don't make this a factor in buying a bike. Get a bike with the best frame you can afford. The components WILL eventually wear out and then you can upgrade to whatever you prefer or can get on closeout!
you know, one thing i like about even the least expensive sram gripshifts(MRX) is their quickness. as long as you ease off the pedals just to maintain your rev's, you can shift the rear from the highest to the lowest gear, in the turn of a wrist~ rapid fire has a max of three gears in one push of the thumb, but that's only for shifting down for, say, and uphill climb.. you're sorta limited there, and even that's only on the higher models. this is the major difference between grip and rapids...
AND, with the sram friction system(smaller increments in the turn of the shifter), there's a lot more leeway for derailleur adjustment... i've found that gripshift, if necessary, can work even after the most sloppy adjustment job~
In regards to SRAM shifters compatability with Shimano deraillers, I have garnerend the following info from SRAM's website (Someone correct me if I'm wrong) :
The "GripShift D.I.R.T" line (MRX, Centera, Neos, Quarz, Plasma) are designed to work with Shimano componants as well as SRAM D.I.R.T. stuff.
The "ESP" line (5.0, 7.0, 9.0, 9.0SL) only work with SRAM ESP componants.
I have the Gripshift MRX with Shimano Acera on my bike and they work great for entry level stuff. I'm going to upgrade soon, though, i can't decide if I should go with all SRAM ESP or stick with Shimano deraillers and the Gripshift line.
Has anyone compared the ESP deraillers to Shimano stuff at similar pricepoint?
I hear what Sram says about compatability, but what does the word compatable mean? That it works as good as possible? Works most of the time, or some of the time? In My experience, I have had alot of trouble making Twist shifters work very good on shimano components. Then when the twist shifters get a little old they are worse.
Has anyone had similar troubles?
oh, yeah, and one more thing: have you ever taken a gripshifter apart? the first thing i notice is... it's CHEESINESS... all plastic, no bearings OR bushings anywhere, and then there's more plastic!!!... i hear you.. after you use them for a while, no wonder they get worse.
I have twist shifters and i hat them i am always accidentaly switching the gears. i rode my buddys bike and he has rapid fire shifters and i would take them over mine anyday. But i guesse its all preference