I have owned both decks in the past.
The Studer B67 is a real pro deck.
The TASCAM 3440 is a semi-pro deck.
Like the other post said, the Studer is probably a 1/4" 2 track and the TASCAM is a 1/4" 4 track.
The Studer will probably run at 7.5, 15 and 30 IPS.
The TASCAM 3440 will only run at 7.5 and 15 IPS.
With a bit of effort you could get a set of 1/2" guides and 1/2" heads and conver the Studer to a nice mix deck.
The TASCAM can't be converted to anything.
The Studer will let you easily set upn calibration for either NAB or IRCC equalization curves.
The TASCAM is a HUGE pain in the ass to calibrate at all and has all kinds of compromises that TASCAM/TEAC was famous for.