To the OP - I feel your pain, but from a slightly different perspective.
I recently did my PPL in Florida. Whilst many people still seem to carry a 'perception' or 'view' about the Florida PPL's I must say that this thread is testiment to the what is easily the strongest selling point for the Florida PPL.
I did my PPL in 18 days from start to finish including my Night Rating!
Yes I admit that I have had to have lessons since coming back to learn the UK way of things, but I only needed 3 lessons and am now enjoying the freedom of solo flying in the UK. Hang on, did I say 'freedom'.....?
Now, onto why I feel your pain. Since being back, I have had 5 flights, 3 with instructors and 2 solo. I have also had 5 flights cancelled due to the weather!! A 50% hit rate, and if I didn't have the luxury of being able to duck out of work for a couple of hours for 2 weekday flights this would have been only 3 flights and 5 cancelled flights so this would have been a 62.5% cancellation rate. In the last 2 weeks the weather has been so bad that at times I was feeling so depressed and hacked off with it that I wondered if flying was for me. Rather than feeling good about being a pilot I was just feeling miserable all of the time, and for the first time in my life I have started to consider the prospect of moving abroad!
The problem you will inevitably have is that you will waste quite a few hours going over stuff you have already done in order to refresh and remind yourself due to the long time period between lessons. In my mind this is non productive and just a waste of money. I would say that doing a PPL in 18 days may be just a little too fast as you really don't have the time to fully take in what you learned from the previous flight before you move onto the next lesson, but having the ability to fly consistently with never more than a day or so in between is a very productive way of doing things. Not to mention the fact that I probably saved about £2k all in and I think the advantages of USA flying speak for themselves.
If I were you, I would jump the pond for 4 weeks and get your PPL done. You will absolutely love the freedom that US aviation offers, you will avoid the frustration of constant delays and cancelled lessons, and you will fly home with a PPL and will feel on top of the world.
Good luck to you and hang in there. It really is worth it, and whatever route you decide, fly safe, fly smart, and I hope you can join the PPL club soon.