Los Dos was the name Cannondale gave to it's off-road tandems back in the early to mid-90's. They dropped Los Dos towards the end of the 90s and simply marketed their off-road tandems as the MT-800, MT-1000, MT-2000, etc...
I'm not sure there's a direct, comparative model offered by Cannondale here in the US; the Street Tandem would probably come close to an entry level Los Dos.
Cannondale had a Mountain Tandem in the US up until 2006. They now have only the Street Tandem, which shares the frame with the old Mountain Tandem. The largest difference was tires and disk brakes. The current Street Tandem can accept both, but will require a new wheel set for the disks. Tabs are already included.
My wife and I have a Los Dos. We use it as a backup, loaner and for riding The Great Allegheny Passage/C&O Canal trail. Have had no problems at all despite lugging 4 panniers worth of camping gear, clothes etc. for over 300 miles of limestone trail.
Not sure what new bike would be comparable. But if you can find a Los Dos used in decent shape, go for it!
what is a cannondale los dos and are they a good tandem bike also what do they compare today thnaks
We had a Los Dos which we bought in Costco, Atlanta in the eary 90s for $1000. It was never a good fit for me (my fault) but was well made and equipped and had 27 speed Tiagra, 26" wheels which I eventually shod with 1" slicks. I sold it about three years ago for $525. A good starter bike in my opinion.