I personally like the clean look of a glass cabinet without a mullion, but perhaps you can order a removable mullion from your cabinet manufacturer? One of my cabinets came with a mullion that was removable, and I replaced it with clear glass.

I would not order it online because if there's a problem with the glass fitting, or with the cabinet door, you then have two problems. We took our cabinet doors into the local glass place for fitting and they decided one of the doors was too warped for glass. The cabinet company replaced the door and we then had the glass installed.

Nyrgirl35 - Just regarding the mullion - I had 4 glass cabinet doors with mullions and I took them out and exchanged them for glass doors without mullions. It was an expensive switch, but I couldn't stand the mullions. You can never line up the shelves with the horizontal mullions, and if you can, it will not look lined up from a different vantage point. I know it makes me sound crazy, but believe me, it was so annoying. What a relief to get rid of those mullions.

I had a neighborhood glass shop do the glass inserts for my cabinet doors. I brought the doors in, picked my glass style, and came back a week later to pick up the doors with the glass installed. I don't think the shop was was much more expensive than online, and there were none of the hassles I can imagine from ordering glass inserts online, shipping them, and installing them. I also like dealing with the nice local shop.

In my experience, it was much cheaper to get glass from a local glass place than to buy cabinet doors that came with glass. It also was much easier to find the look I wanted. Glass shops can do anything, but cabinet lines only have so many options.