Hi all. I have an Isoflo CL170 cylinder with good few years life left in it in my system which has performed trouble-free other than the odd new immersion element. I'm getting a new ASHP fitted and the installer is recommending scrapping the Isoflo and replacing it with a Secon Trade Heatpump cylinder (unvented, 170 litre), which they would supply. I suspect the argument is that its heat exchanger is designed for the the lower flow temperatures from the ASHP, whereas the Megaflo expects higher flow temperatures to its heat exchanger. A couple of questions: Is it worth the additional cost for what may be a marginal benefit? Is Secon a reputable make - I've no experience of them, nor heard of them. Thanks!