I was in the same position as you a good while back and same size as well. I did try the flexi's but managed to get a Libre special for a discounted price and it carries my 100kg so much better. This is particulary true as I got more skilled in the buggy and started to throw it around a bit, the extra strength, axle width, more comfortable seat all made me appreciate why it cost that little bit more.
Good luck with whatever you end up getting.