3 bed flat in London suburbs (Hayes) or 3 bed house in Bishop's Stortford? Or remain where we are?

[confusedperson]

Hi, I would appreciate your opinions. I have two boys, 4 and 2 yo, currently live in South London and do not particularly like it (but don't hate it either). However, we are worried about secondary school choice in few years time and will have to switch to 3 bed from our 2 bed terrace. So, the options within our budget are:

1. 3 bed modest house in Bishop's Stortford, a good secondary almost guaranteed (because apparently they are all good) and daily commute to the City for work (time-wise OK but the cost is a compromise).
2. 3 bed spacious flat in Hayes, an outstanding secondary nearby, convenient commuting, nice area... but a flat!
3. stay were we are.... not really an option but we have a chance to get in into couple of good and upcoming Harris academies, of course it may be rough on the edges, excellent commuting, nice area and road, but my boys will not fit into their smallish bedroom in few years time... so yes, we probably have to bite the bullet and move (as much as I love stability).

Any advice on which option seems the wisest? Unfortunately we cannot have everything, so we need to compromise and I am looking to hear from people that have done a similar move.

Thanks!

Stortford is lovely, we moved there from Uxbridge and never regretted it. Schools are all pretty good too.

I'd go for the house option, so Bishops Stortford.

House for me. Have done the flat-with-child thing and I'd do a lot to avoid it again.