I don't know anything about these rifles other than I've seen one Dakota and it was very nice. Heres what I found on Dakota's website:

Individual Traveler rifles can be built in virtually any caliber; however, multiple barrel/caliber combinations must be chosen from within the same family of calibers.

Calibers and Actions

"a" family
.257 Roberts
.25-06 Rem
6.5 x 55
7x57
.270 Win
.280 Win
.30-06 Springfield
.338-06
.35 Whelen

"b" family
7mm Rem Mag
.300 Win Mag
.338 Win Mag
.416 Taylor
.458 Win Mag

"c" family
7mm Dakota Mag
.300 Dakota Mag
.330 Dakota Mag
.375 Dakota Mag
.404 Dakota Mag

"d1" family
.300 H&H
.375 H&H
.416 Rem Mag
.458 Lott

"d2" family
7mm RUM
.300 RUM
.338 RUM
.375 RUM

"e" family
.338 Lapua
.416 Rigby
.450 Dakota Mag

"f1" family
.270 WSM
7mm WSM
.300 WSM
.325 WSM

"f2" family
7mm SAUM
.300 SAUM

"g" family
.243 Win
6mm Rem
.250 Savage
.260 Rem
7mm-08 Rem
.308 Win
.358 Win

Hope that helps. I love takedown rifles.