Would we be better off switching to UC?

Can anyone maybe give us some advice as we have heard we would be better off switching to UC. We have heard also that our rent would also be paid if we got UC.
There was a number we called a while back and it gave you a free benefit check to see how much or not better of you wouod be if you switched to UC but lost the number. It seemed to be a Scottish based number and one geared towards encouraging people to switch to UC.
Anyone know it? Or of a similar one?

Also I have been assured that I would keep my ESA contribution based benefit as a stand alone and side by side of UC, is this still correct? What about my own DLA which is still managed by the UK office rather than the Scottish Gov which have now taken over the Children's DLA?

Here's our current circumstances.

*We live in Scotland.

*Two disabled children under 10.

*Mrs works 25 hours per week and earns £27,857 before tax and NI.

*Myself gets ESA contribution based

*Myself also get DLA middle rate care / lower rate mobility
.
*Two children get Scottish Disability Payments (Scotland equivalent to DLA) which is both get lower rate care / lower rate mobility but have appealed for one of our daughters to get higher rate so waiting on that.

*Child tax credits

*Scottish Child Payments

*We pay private rent of £643 per month.

Would most appreciate any advice.

Thanks all