Please help me decide on a model. My back is killing me as I have a bad back but have pretty rough ground to mow. Wanting to get a Ferris due to the suspension. I demo'ed an IS2000Z, it was fine. The engine did bog down a few times in taller grass and didn't like it when the blades engaged but otherwise it was comfortable. I like the idea of the IS2100Z with the larger tires and other updates, plus it was easier to be accurate around trees and structures with the new integrated transmission, but the ones they carry locally for $8,400 are 26 hp vs. 29 hp on the one I borrowed. So, I'm concerned about the power a little, losing 3 hp from the one I tried. The next step up is an IS3100Z with a 36 hp Big Block, but we're talking about $11,800 plus tax. With the fees and tax I'm looking at a $265 payment, which is just kind of pushing what seems to be sane in my opinion. Strangely, just jumping on the back of one, it actually flexed less than an IS2100Z, but I'm not sure if this is telling of anything. I guess I'm mainly wondering, is it really worth a nearly 50% upcharge from a 26 hp IS2100Z to get the true independent suspension and a 36 hp Vanguard big block? There is a third option, basically there are a few IS3100Z's with a 30 hp Briggs Cyclonic engine for $8,500-$9,000 depending on the dealer. Is this the thing to do or is that too little of an engine for that big of a machine? From what I can tell, an IS2100Z should suit my needs just fine but I'm afraid I'll kick myself for not going bigger. Thoughts?