Really all depends on what u want to do
Commercially u can't go wrong with kubota,exmark,bobcat,scag,gravely,Deere,toro,hustler,walker personally I would check like an earlier post stated see what all brands are in your area so when it goes down ur close also for parts u might be back going in a few hours instead of a few days
I just got rid of a bobcat 10 years old 1500 hours and had the hell run out of it and still going strong
I've went to a kubota zd326 diesel 60" and it is a awesome mower if ur looking at a mower to cut turf walker is very hard to beat I have 1000 hrs and still running strong just my 2cents
Probably ur best all around mower as far as gas powered exmark lazer z. Well built, cuts and leaves a good stripe, parts are pretty reasonable very well built and durable
Hope this helps