Hot water pipe Insulation

[kraghum]

we are using Ashirvad flow guard fro hot and cold water pipeline for house, plumber is of the opinion that we do not need any insulation for hot water pipes of this variety. is it the case. few folks (solar water heater seller) i asked say just go for insulation since there will be still some radiation loss will be there for water which is stagnant in pipe line

Please comment your experience
Raghu