Recreational & Family - Upgrade or buy new bike (Help)

My daughter has a 2 year old Diamondback Outlook Mountain bike. She loves it now that we took off the knobby tires and replaced with a smoother "Road Tire" since she rides streets and rail trails with the family. She rides like 15 to 20 miles a week with us (Family)...

The question here is she can NOT stand her shifter mechinism on the bike. It is a "twist/shifter" on the hand grip(s). She envy's the Wifes new Raleigh Detour 4.0 with quick fire/trigger type shifters, as well as my Passage 4.0 that I got a few years ago... What to do, what to do!

Do I buy her a new bike, or can a LBS remove/replace to these types of shif mechanisms as it is a "got to do something" scenario.... She will NOT shift, and come to think of it, she has not shifted since getting the bike? Nut's!!!!! but she says it is too hard to get it into gear with her current set up. I even had the LBS test/trobleshoot her existing set up to "prove" there was nothing wrong-. None the less- new bike or do I just change the shift option? She rode my wifes new Detour and was shifting like mad?
Help me out?

I would say it is time for a new bike as she has probably out grown the one she now has.

If the bike still fits her, your bike shop can install trigger shifters. I'm trying to think through the cost here. Jenson has 7-speed, Alivio shifters for $25/set, though a bike shop might charge a bit higher than that. Figure new cable and housing at around $15 or so. Not sure about labor cost. Possibly you'd need new grips after getting rid of the twist-shifters.

Thought someone would go that route? So new bike, Raleigh passage/detour/route-09 is 380. at local bike store. She is riding more and more and so much to the fact my Mother is getting (giving) her an old Nashiki road bike for true road use...

Any other opinions on swapping out gear shifters?

If the bike is really a good fit that is the most important thing. New bikes are great but if she has something that works, geometry wise that is hard to replace. I say take it to the LBS pay a few bucks and have them switch her to trigger. You get to reuse existing equipment and she stays happy.

The trigger shifters are nice. I've been thinking about this for my daughter's bike, which is just an ultracheap Kent. The thing that stops me is the thought of how many components I'd end up replacing:

Shifters ~$25
Cables & Housing ~$15
Grips ~$10

That's probably all you need with the Diamondback, and it's probably the way to go if the bike is otherwise satisfactory. If you aren't comfortable doing this yourself, you might be looking at another $50 in labor and shop fees.

In my case, the existing components are pretty crappy, so I'd be looking at replacing a few more things:

Front Derailler $15
Rear Derailler ~$15
Freewheel ~$15

At this point, I'd be spending in the ballpark of what the bike cost new, but still under what it would cost to replace it with something decent. I'll probably wait for her to outgrow this (my daughter is 10), and then get something better.

Thanks for the replies so far. Money (not that I am rich by any means) is not the bottom issue with me, I NEVER had a nice bike growing up and as a 10 year old, I pledged to myself MY KIDS would ALWAYS have nice/cool bikes...

Anyhow, the issue is somewhat keep the Outlook (Diamondback) and put 100 into it, great and no problem. But we all know how teens are. Is this truly a complaint on shifters or is it a I want a new bike so I'll claim this is the root issue.
Mom and I both have great Raleigh Passage/Detour bikes and we ride them! I am doing GOBA next spring with my youngest on a tag along (60 to 80 miles/day- 6 days) and my wife and daughter car camping along with us and doing rec rides in the evening. I am wondering if this is not a ploy for her own Womens model of a Raleigh???

I am going to ask my daughter her opinion on upgrading these components-

I am paying the LBS to do the installation as other than a flat, I do not do bike repairs...

Thanks

Thanks for the replies so far. Money (not that I am rich by any means) is not the bottom issue with me, I NEVER had a nice bike growing up and as a 10 year old, I pledged to myself MY KIDS would ALWAYS have nice/cool bikes...

That being the case, I'd go with a new bike. :D

I am going to ask my daughter her opinion on upgrading these components

I think that's a good idea. Maybe loat the "new bike just like mom and dad's" idea by her. See how she reacts. I can well imagine a 10-year-old wanting a bike just like yours.

Come to think of it, my own son is not much different. I have several Specialized bikes. But for awhile my son was on a Giant. He was very thrilled when I bought him a Rockhopper last year, because now we share the same brand. This year I made the big move to the 29er wheel size, and now he also wants to move to 29ers.