Tony: Thanks. Pretty sure the Smart Guage system is calibated OK, the Link 10 and my own Multimeter all show similar volts about +- .05v.
I have used some 135 Liesure from Mid**** Swindl***. These were at 42Kg, Wt being historically my criterion as a choice for batteries. However a mate "in the know", tells me it is the thickness of the plates that counts. That is fewer thicker plates rather than many thin plates (starter) that give the higher available discharge and number of cycles. My 135s he reckons are only good for 300 odd cycles and on a floor of 50% discharge. Deep Discharge, good ones 1500 cycles and down to 30% discharge. If I could fit (Space) I would go for 2nd hand traction 2v which apparently go down to 10% and his are now 12 years old!
Problem with looking at the wt. is I don't know what it is made up from, lots of thin plates (Starter), fewer thicker plates (Leisure) or a very few thick plates of the Traction/Semi Traction type. I cannot get any difiniative answer to where the battery lies on the starter to traction continuum, they does not seem to be an industry std. Just a lot of Marketing. Any advice, the Powerline, a branded Trojan look attractive, but what is inside!!!!!!