I don't have any direct experience with the LS line. I bought my Kubota
L3700SU last year in Taylor, TX. It is most comparable with the I3040H on RCO's website except for the same price I also got a hardtop sunshade, landscape rake, delivery and 50 hour service labor.
I got quotes from a number of dealers on various tractor packages in the same category, including Barlows and a couple other national dealerships. I took those in when I went to my local dealer to talk a deal. I always prefer to buy local, but I was willing to go mail order if the local dealer could not match my best internet deal. My final package was tractor, loader, 5' rotary mower, 5' box blade, 6' landscape rake, hard sun cover, drawbar package, free delivery, and parts only 50 hour service out the door for $19,500. Given my deal and what I can see on RCO's site, I think your deal is a little overpriced...but maybe conditions are different between Bastrop in 2010 and Dallas in 2011. It is within a 1-1.5k of what I would think would be the magic number.
From what I have heard LS is considered a reliable brand. As long as the dealer can stand behind it and stay in business I would not shy off the deal for that reason. I like Kubota mostly because of the impression my dealer made when I visited his shop. I did not have any brand preference prior to that.