Use a Ctec MXS10 myself, always powered up on my GS for the last 9 years without problem.Afternoon all. My CTEK MX10 failed after 13 months and after a bit of hassle, Amazon have refunded the cost. I use this almost exclusively on the GS and am wondering if this model is slightly overkill and a 5 or 7 amp model would suffice. Thoughts appreciated, thanks. Richard