As cugila says, they're a great snack. I'd suggest testing to see whether you need any insulin for them; you might not if you're only eating a smallish amount, but it's worth testing. I know I personally need a unit of insulin per 30g cashews, but of course it varies from person to person.
Most other nuts have far fewer carbs and might be "better" choices in terms of your control, but there's no getting round the fact that cashews and peanuts just taste far nicer than other nuts!