My brother has a KLR 650 and I rode with him a few times while I had the Burgman 400. One ride with both him and my other brother on his BMW 1200R they put me in the lead because I had the "little" bike. After awhile I had to drop my speed because the cross winds were affecting the one on the KLR much worse than either me or the one on the BMW. Later my brother on the BMW asked me why I slowed down and I told him I seemed to keep losing Dave (KLR) in my rear view mirror. To be old that "yeah, I had that same problem on the ride up to meet you."
Okay, that's my fun poke at someone riding a KLR. There are many, many places where the KLR would be the much better choice (speaking as someone who dumped a Burgman on a gravel road, they do not handle well on somewhat lose light to moderately graveled dirt roads) but they are very good on the highway and handle winds well. Acceleration is smooth and you can cruise all day long 70-80 miles per hour and still have grunt in reserve. I've ridden one between Houston and Breckenridge as well as other long 1,000+ mile rides. Care does need to be taken on the throttle or you will find yourself going in the mid 90s without even realizing your going that fast. I'm speaking of 1 up. Nicest thing about the Burgman 400 was taking a 3-4 day trip and having everything fit under the seat. No saddle bags, top case or even a net (one of which is included with the Burgman 400 and it has connection knobs discretely tucked under the tail to attach it without using hooks that could damage paint.
Negatives for me was the seating position and low speed handling but I'm used to and prefer more upright seating. So we traded in the Burgman for a BV 500 which still isn't quite as good for distance riding as my Scarabeo 500, same engine just different suspension, seat and body panels but the differences in ride is enough to be noticeable. Check around some dealerships will let you rent a used one if they have one in stock. (I've seen a few that don't call it a rental but a conditional sale. You "buy" the bike and can return it within 10 days for a "restocking" fee.) That would give you the opportunity to see if it is one that fits you or not.They are a good scoot and if you don't go off road or do dirt/gravel roads then the Burgman would be better for touring than a KLR but that's just my opinion. I'm a road not off road rider so what do I know.