New X300 owner,Are they good mowers? Owner Opinions

Last week I purchased a new X300 48" cut mower.My grass is not high enough to cut yet so I have not used it,it has .2 hours on the clock. I was hesitant about the purchase,I had to dig deep to pull out right out $3600 including tax.It does have the JD 30 day promise.The only issue I have is when unloading it off my trailer I noticed all the tires have bad splitting on all the tires around the tread,it was in a crate at the dealer and looks like the tires were flat and they cracked.I let my dealer know but he has been very slow about resolving this,sent him pics and he says he has to contact JD Corp but after 2 emails and 2 phone calls to the salesman he has not contacted me which is making me wonder about service after the sale.As far as the mower are they good mowers if maintained? I like the feel of the mower,it handles well what little I drove it,the Kawasaki is smooth running.I hope I made a good choice.My old mower is a 15 year old well maintained Craftsman with a 15.5 Kohler Command 42" which still runs fine but the deck is thinning along with a few minor issues. All I know is there is a huge difference between the JD and my old mower.I'd like some owner opinions of their X300,how many trouble free hours,tips,advice ect.. Thanks