Mountain Biking - Which do you thing is best?

I'm gonna be 64 years old. For 10 years I've had a pretty nice Gary Fisher Hoo Koo E Koo mountain bike. I do a lot of mnt biking, but lately, I've been doing a lot of road riding to (20 to 30 + miles 3 days a week) and keep meticulous records of distance, speed, average, etc. On a good day, the best I can average over my 20 mile road course (mostly flat with a few small hills and riding non-stop) is 13.53 MPH with my mtn bike. Because I'm doing so much road riding, I'm thinking of getting an entry level road bike. I've got it narrowed down to these three. A 2008 Trek 1.2 for $595. A 2009 Raleigh Sport for $520. A 2008 Giant Defy 3 for $585. I road them all and they all seem like nice bikes. Naturally, each LBS claims that the brand he carries is better than the rest. They always talk about "components". I don't know how to interpret the specs on these three bikes. Is one of these three really better than the other two. Or are they all about the same and it just boils down to personal preference. Which bike would you choose, and most importantly, "why".

Trek 1.2 Specs: http://www.trekbikes.com/us/en/bikes/road/1_series/12/
Raleigh Sport Specs: http://www.raleighusa.com/bikes/road/sport/?page=specs
Giant Defy 3 Specs: http://www.giant-bicycles.com/en-US/...ad/2266/32193/

Although my Gary Fisher Hoo Koo E Koo mountain bike is now 10 years old, it is very comfortable, totally reliable, and I really like it. Over the years its become a trusted "friend". So another idea is to put on some high psi mbt slicks like one of these:
http://www.bicycletires.com/pcocug/c...inch%29/pp.htm
http://www.bicycletires.com/pcocts/c..._26inch/pp.htm
100 PSI Kendra Kwest: http://www.kendausa.com/bicycle/commuter.html
I'm leaning toward the Kendra Kwest.
I realize that this change won't turn it into a road bike, but will it make a noticeable difference?
Your input on this idea would also be greatly appreciated.

Thanks for any input you can provide.
Don

Kenda

The Trek has a very slightly better spec. Sora vs. 2200 components. Go with the bike that feels best and the LBS that treats you best.

Slicks will make your Fisher roll faster, but like you say, it won't be a road bike. I'd go much cheaper on the tires.

You might want to post this in the 50+ forum.

The Trek is by far the best. It's using Sora instead of 2200, which is slightly better. Plus, it's using the new Sora which is 9-speed instead of the 8-speed old Sora. The Trek is the best bike there.