Hi, I would say,and evidence suggests that there are no advantages in changing to Lantus/Levemir from NPH. Of course medics will tell you otherwise, but just read the amount of postings on this forum from people having problems on Lantus and Levemir, It is not the best option.
My advice would be stick with a long-acting NPH or try animal insulin. You DO have a choice, and should not be pressured by your doctor into taking analogue insulin. I was told,while on Insulatard, that Lantus would give me good control. Instead it destroyed 4 1/2 valuable years of my life, and that is no exaggeration.
Lantus and Levemir clinical studies only lasted 28 weeks maximum for type-1. These insulins are not proven safe in pregnancy or for young children, as they were only tested on rabbits and mice, and both companies state they should only be used in pregnancy "if clearly needed". The info is available on the Sanofi Aventis & Novo Nordisk websites, and is a bit of an eye opener, and a worry.
GM in relation to food has become a dirty word. Perhaps if the term "GM insulin" were used for these insulins, instead of the misleading terms "Human Insulin" and '"insulin", which they are not, people would think twice about taking them, and be better for it!
You've asked the question "which basal insulin to ask for?". I can't tell you what insulin to take,but from my experience Hyprurin Porcine Isophane is superior -with it I have the best control I've ever had in 20 years as a type-1.
Jus