Just wondering if anyone had any experience of using one of these, and if they’re any good. Thanks https://www.amazon.co.uk/Switch-Sticks-Legged-Bubbles-Design/dp/B0073EK2MC/ref=mp_s_a_1_1?ie=UTF8&qid=1548499278&sr=8-1-spons&pi=AC_SX236_SY340_FMwebp_QL65&keywords=walking+stick+with+seat+folding+lightweight&psc=1