Only quote once be ready to do a bank transfer the whole amount, and hope for the best
I ended up accidentally with 3 quotes as finding your past requests is a little tricky to begin with. I made the transfer for one of the quotes in three batches as my bank had limits on how much could be sent via faster payments. I received notification the money had been received and then nothing...After several days I got in touch with them to ask where my money was. They quickly rectified the issue (but leaving tens of thousands of pounds in limbo without spotting it hadn't completed is a little worrisome). And now they have declined my cashback, despite submitting the reference for the quote I did complete.
Would I use them again? Yes as the rates were very competitive even without cashback.
Would I actively recommend them to other people? No as I wouldn't want a friend to blame me for any heart trouble caused due to funds not arriving as expected.