I gave birth at Whipps last year (EMCS), and was readmitted to Newham (as Whipps had no beds) with DS 5 days later (for him, not me).
I much, much preferred Whipps. It doesn't look as modern and the care we received was by no means perfect, but I felt it was a much friendlier hospital and, with the odd exception, the staff were lovely.
Ante-natal care was fine, mostly done by community midwives who were great. It's a very busy hospital, though - not that it would affect you but the birth centre was closed due to staff shortages last summer.
Newham looked much more modern - we were given a private room - but the midwives ranged from unhelpful to unpleasant. Some were very undermining to a new mother, and one actually shouted at me for not dressing DS fast enough... The doctors, on the other hand, were fab.
We were readmitted due to feeding issues and weight loss, and received no feeding support at all. It was very disorganized and some of the staff didn't even know which one of us was the patient. You couldn't pay me to go back there. Clinically, DS received perfectly appropriate care but the atmosphere was downright unpleasant.
I hear good things about the Homerton. There were some worrying stats around their maternal mortality rate when I was pregnant, but that may well reflect the complexity of some of the cases it handles. They have a NICU as well, I think - I know of premature babies in my area who started at Homerton but were transferred to Whipps as they improved.
Tours would be a good idea! You'd also be able to ask how they would approach your care, especially if you are planning a VBAC, as I understand that can vary wildly between hospitals. Good luck!