Sheffield Aero Club worked for me.
Netherthorpe is a well liked and friendly airfield and its well known 'tolerances' force you into being accurate and on the ball. Taking off massively overloaded or floating down the runway for a couple of hundred meters are
not allowed, as testified by the assorted PA28 shaped holes in the hedges.
Hour builders: No hour builders at SAC, just professional instructors with a tens of thousands of hours. I can't speak for Phoenix but I'm sure that you can ask. There is a general shortage of instructors nationally so situations change.
Weather: It's the weather in the air that usually stops you flying. The grass runways at EGNF are in excellent condition, generally reinforced where it gets muddy and rarely closed in my experienced. There are four of them so if it's flyable you should be flying. Obviously winter can have an effect but I learned over the winter / spring and there was some fabulous flying with fabulous vis, and quite a few challenging days when I was glad to have an instructor showing me how to cope!
Aircraft choice. You'll be training in a two seater so it's either 152's at SAC or 150 aerobats with Phoenix. There's nothing in it for PPL training. Both seem to keep their aircraft flying rather than tech. You won't be worrying about four seats for a while.
Costs: You pays your money and makes your choice. Both will teach you to fly but this is where it starts to get more complicated. Phoenix flyers are simply not allowed in the (very very good) SAC clubhouse or outdoor viewing area at all unless they join SAC. I had an awesome £4.95 Sunday lunch at the weekend, and sat chatting aeroplanes in the lovely warm clubhouse. Phoenix, take sandwiches.
The difference in costs is basically down to the fact that SAC own and operate the airfield, and Phoenix have no facilities to speak of, and they do their own maintenance. Both are cheaper than most places. If you're worried about the small difference in costs do not get a Transair / AFE / FlightStore pilots supplies catalogue.
Instructors: I find the SAC instructors and staff to be very nice people who are good pilots and instructors. I've no experience of the Phoenix mob but I'm sure that they are perfectly normal single headed people too.
SAC is a club, Phoenix is a school. The differences will become apparent over time. If you want a cheap licence on the way to an airline job then any old PPL will do, but if you want to stay on airfield afterwards I'd get into a club. SAC has various groups that are active in aerobatics and air racing There's also more scope for getting into a group for touring if that's your thing.
It all depends on what
you want out of it! I chose the Club and of course I'll stand up for that decision, but that's not to denigrate the School in any way.
If you want to know more or drop in for a chat when I'm there feel free to drop me a PM.