Its hard to make a recommendation without knowing what conditions you live under, Tahiti is different from Nome
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I tend to lean towards anything that makes turning easier, I do a number of short driveways each year and turning fast and easily has a big effect on how fast I can do the job. The Platinum has ATC which is not explained on the site but I think it means a true differential where both wheels get appropriate power while turning, this was a feature found on all "D" models which were predominantly in the "Pro" line. The Deluxe has a remote locking axle which is also not explained but I think means there is/are one or two triggers on the handle bars to release one ( or both, not sure) wheels to allow easier turning than having both wheels locked to the axle. The differential has been considered the "top of the line" for ease of use, whether it is worth the premium paid depends on the individual user.
Battery powered electric start has never appealed to me. Most of the time my machine starts after one or two pulls so electric of any sort hardly ever helps. When I have benefitted from electric I was using the 120V version, plugged into the wall, to get a neighbour's balky engine going at the beginning of the season, after that no real problems. My experience with batteries in general is that if you don't use them regularly through out the year they either die or require careful maintenance. That tends to be more trouble than its worth in my mind for a snow blower.
The only other difference that jumps out at me is the 24" swath as opposed to 30". What you are clearing comes into play. If you figure on loosing 2" per swath due to overlap then you are clearing 22" and 28" respectively, That means every 11 swaths at 28" is 14 swaths at 22". A hockey rink or parking lot will benefit from a large swath, driveways typically don't. When you do this calculation don't forget to figure out where you want the blower to end up. If the larger swath leaves you at the wrong end of the driveway then you have an extra trip to get back to the garage. Agility and ease of storage also come into play, especially with the large machine.
Personally I found the Ariens site confusing, lots of marketing BS with less than stellar descriptions of what the features actually are, here is an example from the "Deluxe 30 Overview"
"Always on the attack, this machine features a heavy-duty XS Gear Case™ that provides additional power…especially in extreme snow conditions."
- "Allways on" - Personally I want to turn it off when I'm finished for the day, doesn't it run out of gas at some point;
- This is a snowblower it doesn't "attack" anything;
- How does a gear case "add power"? Does it have an extra motor, flux capacitors, Mr Fusion home energy kit? I'll give you that an efficient gear case doesn't loose as much power through friction and mechanical loses as an inefficient one but the last time I looked at the third law of thermodynamics says you can't create energy from nothing and you must loose something;
- The last question about this statement is how does the gear case sense that you have "extreme snow conditions" so that it can break the the third law even more than usual?
