Levemir is not equal to Lantus. You have to shoot Levemir twice a day to get the same performance. So is Lantus the better basal insulin? Boldly not! Here is a quote from another discussion:
With high dosages the Lantus shows more constant delivery but in most cases the duration will not reach 24 hours. Thus it is no miracle that Lantus users have problems at least one hour before the next shot. Some circumvent this by adjusting their insulin factors. But this makes it impossible to skip the meal at that time because a portion of the bolus insulin is used to replace the degrading Lantus. More badly is that most user try to increase their dosage to reach 24 hours. As a side effect they have lows in the night for example (probably many undetected lows). Another problem of Lantus is that it will connect to the body tissue and from there it is constanly released at a slow rate into the blood stream. If you hit a blood vessel and inject the Lantus there it will not connect fully to the body tissue. Thus several Lantus users have experienced sudden lows after their Lantus injection.
At the last diabetes fair in Germany I asked several diabetes trainers about the claim of Levemir to last for 24 hours. Most of them said that Levemir is a very stable and good insulin and should be taken twice a day for optimal performance. None of them thought that one shot is sufficient for type 1 diabetics. I really wonder why your medical team needed a CGMS to find that out!
I am using Levemir too and I think it is the best basal insulin you can get. It will connect to the albumin of the blood first. From there it is released constantly into the blood stream. This connection to the albumin is very much preferable to the tissue connection of Lantus because there is no risk of having a low by injecting into the blood stream. To need two shots is a little more work but you will be rewarded with a real 24 hour coverage. Furthermore you can adjust your dosage for example for the night to compensate for higher physical activity on that day. Most Lantus users do not adjust their dosage at all but with the two shot regime (every 12 hours) you will have more flexibility for fine-tuning.
It is also possible that two shots of Levemir will help to prevent the lows you are experiencing with Lantus. I know some people in this forum who had severe lows with Lantus. Maybe you can contact Katherine (Marps) to ask her about her experiences - she switched from Lantus to two shots of Levemir.