Muswell is a funny one. Too long to sprint up, easy enough to start and then just gets continually harder. Not sure if it's a mental thing with me but …
Be aware - this can be highlight but warning at the same time as well. :) It just depends what do you look for. Muswell hill is great climb with average climbing grade 9% but has segments with 13% as well. Great thing about this hill is that ascent is exatly 50m. So if you would like to do Mount Everest challenge you would have to climb this hill exactly 177 times. :) Have fun!:)