As nailed said, topline should be muscle, not fat. To get muscle you need good quality protein in the diet and appropriate training. There is no such thing as a bag of feed that builds topline on its own. Unless the horse is fat!
she has Pink Powder and Alfa A Oil along with No 17 Outshine and No 11 cubes as she needs energy as she is a rather laid back character.
I am going to rough her off at the end of November and was going to replace the race horse cubes with the conditioning flakes so as to keep her weight on as she will never be a fat horse but since being on the diet has held condition well through a very competitive season
The super conditioning flakes ARE heating! I use them on my main event horse throughout the BE season as he performs well on them, but is very fired up in all ways. He comes off them as soon as the season's finished as I need him calm and reasonably sane for the winter.
If you're wanting topline, put in the effort with your horse, but definitely try TopSpec balancer.
They haven't hotted up my OH's TB, who was absolutly barmy on barley. I also fed them to my weanling when she looked poor last year, and they really worked on her too.
For poor doers, they give a boost alongside the balancer.
My 25yo mare has been on them for a while now and shes always looked super on them. Shes a hot head at the best of times and never boiled over with them.
i dont find them heating at all. cant feed any other mixes to my nutty orange horse, but he gets a big scoop of these every day and is absolutely fine!