yes, I've got a mark V too, my personal favorite... but that means he might want to buy the BLING... lets see if we can get more information here... Budget, and other information as outlined below.
The bottom line, any equipment that will get you diving safely is better than nothing at all. Everyone has personal preferences, and you need to rent to try out various types of equipment for your style of diving. Many dive shops rotate, I think 20% of their equipment as current model stuff, so getting wet with it should be possible. If I had an opportunity I would gladly try the Aqua Lung just out of curiosity, I would hate to think I was missing something.
I suggest you start at your local dive shops if you need a little hand holding. I say shops, because every shop pushes a specific brand, and you can probably take the sum of several shops and make more sense of it.
Ordering online is great if you know what you want, but until you have some experience, sometimes it is better to have a local place to go that you can rely on. Many folks offer packages, some probably ok, some probably not. If you want to really determine the exact correct equipment here, then you need to post enough information here so that someone can make some judgements on your planned diving style.
The type of information that might be useful is where you will be diving (Florida?) - and the type of diving you will be doing, like wreck, or if you plan on getting technical (cave) a short distance down the road, etc. How many dives a year might you be doing? The right choice for first, second stage you use for example might depend on water temperature, work load and so on.. I am no expert by any stretch of the imagination, but thoughts and specifics along those lines might help narrow down your choices, and help make the answer become obvious. It might well be worth the work, considering some decent mid to high end equipment that is well maintained could last you 10 or more years.. All of that being said... you can ignore the rest of this post, it is not for you. With this information some folks will give you some great suggestions and ideas. Ultimately it's like buying a car, try them out until you find one you like, the style, the power, the bling, etc. You really cannot lose with scubapro in my opinion.