Is Dohop reliable?

I used airline's website to book. From X to Y via Z.

I was charged 3 times. 2 for 2 flights, 1 for dohop

Connection is guaranteed by Dohop but title of the email Dohop sent me is "Booking confirmation X to Y with Transavia Smart Connect"

Delays or cancellation of your flight

If your flight is delayed or cancelled, Dohop will rebook you on an alternative flight to your final destination. To benefit from this service, please contact Dohop Connect as soon as possible by calling or sending a SMS to ... or by sending an e-mail to ....

Should I be worried? There are frequent strikes in Y

Should I be worried?

Yes. Self connections are generally a bad idea and the so-called "guarantee" has often very little value.

No one can really guarantee a connection so it all comes down to "what happens if you miss it".

This case seems to be particularly problematic since Dohop appears to say "Transavia handles it" whereas Transavia says "Dohop handles it". At least Transavia is a bit more specific about it "https://www.transavia.com/help/en-eu/search-and-book/smart-connect/flight-delayed-or-cancelled".

If it is not possible to find an alternative, Dohop will refund the unused part of your booking. If the new flight does not leave until the next day, Dohop will also refund the price of a hotel room (worth €60) and all meals (worth €15 per meal).

That's really bad. Dohop can simply say: "sorry, we could not find an alternative" and the only thing you get back is the money for the flight you missed. But you are still stuck in Y and have to figure out how to get to Z. Same-day or next-day flight tickets will often way more expensive than your original ticket.

Also: good luck finding a hotel room for 60 Euro close to a popular airport.