You really need to go down to your JD dealer and talk with them. We use one of their premium models (3000GS), but, don't pressure wash as a regular part of business. The Subaru engine, according to propaganda, is superior to the Honda. I really like it. However, Hondas are reliable, so there's no need to fix what isn't broken. The choice is yours. You want the triplex pump. I wouldn't go any less than 3000psi. You'll find that concrete, brick, and decks require more than the 1500psi you mentioned. Get a complete set of tips, including the "power tip". Keep in mind that the commercial stuff is a lot heavier. The one we have is plenty for one man to lift. If I were to recommend, I'd get the same one we have. It'll be plenty to start out with.
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'14 Hustler X-ONE, 60", Kohler ECV749 EFI
'05 Hustler FasTrak, 42", Honda GXV530
'14 Toro Timemaster 30"
'02 Lawn Boy SilverPro, 21"
Stihl BR600 blower
Stihl BG55 blower
Stihl KM55R Combi system
Stihl MS180C chain saw
Echo GT-2000 trimmer
'14 Ariens Compact 24" Sno-Thro snowblower
'08 Troy Bilt Squall 2100 21" snowblower
'06 Chevrolet Silverado
'13 Bravo Star, 7'X12', V-nose