Sorry to hear he had a rough start with the DKA. Are you home testing him for ketones as well? I hope he's started to gain weight again now.
Lantus/glargine is a good insulin. I'm glad to hear you are home testing his blood sugars. The AT meter is a bit spendy with the test strips. Most of us end up using human meters cause that way we can test more for less cost. Here are some tips for testing that might make things easier:
Hometesting Links and Tips. Finding a treat he likes is key.
We have a post here worth reading:
New? How You Can Help Us Help You! If it's possible for you to set up a spreadsheet with his blood sugar numbers, we'll be able to provide more help. If that's a technical challenge for you, let us know, we have people who can help.