I attempted this route on my hybrid bike, which I intend to tour on in the summer. It has fairly rugged tyres, but not mountain bike tyres. I would recommend this route for its often scenic nature, in particular the long stretches of canal locks. However there are drawbacks.
The canal towpath in many places is poorly maintained, and was very waterlogged in places, even though it was a sunny week in March. I wouldn't be surprised if it stayed muddy in the summer. I got stuck in the mud a couple of times! Mudguards are thus a necessity unless you like getting messy! The path was also very bumpy for long stretches, so I would definitely recommend a suspension (I only had one in the seatpost).
Overall, I would recommend this route for its views, and for those who want a mildly-challenging mountain bike route. The slightly downhill aspect helps, but I personally won't be attempting this route on my hybrid bike again!