IMHO, it depends on two things.
First, is your rig properly equipped? If so, then on to #2, if not, well ...
Second, are you comfortable towing in the mountains? Not the interstates, the two lane roads. The Cabot Trail is not what we might think of as mountains in the lower 48, but, the road conditions you'll likely encounter are often similar.
Last time we were there, some of the locals (delivery trucks mostly) were not amused at the pace we chose. So, when we could, we got out of their way. When we couldn't - no pull offs/outs - well, they just had to be a bit patient. We had one straight truck delivering dairy products get tired of waiting and pass us on a double yellow downhill - he must have been on the far side of 70MPH, and a sharp curve at the bottom. Dumb, dumb, dumb. But, we never saw him again.
If you're equipment is ready, and you use prudence and some caution, you should be fine.
'Tis lovely country.
Cheers.