Looking at things like the SR Suntour XCM fork from the D600 on the internet, the XCM is listed as a low-end fork (with the XCR (D606) slightly better). But, that would be expected on a $269 bike which really is scratching the bottom of the barrel.
You should take a discount off of a MSRP with a grain of salt. For you, the bottom line is you're buying a $269 bicycle. Keep in mind, this time of year, companies are clearing out their old stock and bringing in new, and there are good deals to be found on last years models.
For those people that have done a scratch build of any bicycle, it is very hard to keep one's build cost below $269. There are several reasons for this. First of all, it is difficult to match manufacture costs on parts. But, perhaps bigger, there is always the temptation to add little insignificant upgrades.
So, rather than buying $15 ea ($30
pr) CST Critter tires, you might be tempted by $30 ea ($60
pr) Schwalbe Big Apple tires. Maybe double walled rims. A few upgrades on components here and there, and suddenly your budget goes through the roof.
As parts wear out, or time passes, you can upgrade many things. For example, a 9 speed or 10 speed upgrade would be easy enough, but would require shifter, and maybe derailleur upgrades. But, never plan on piling $1000 worth of upgrades on a $269 bike.
There are lots of good deals on used bikes that would be appropriate as commuters, especially if you can invest a little in repairs and upgrades.
I don't commute on a MTB. So, I'd much prefer putting $269 into a nice road bike, or perhaps cyclocross bike. But, there are MTB commuters too. So, don't let your eyes gloss over with the offer of a big discount. Buy the bike you really want, and will meet your goals.
Consider the class of bikes. All the above bikes would make good entry level MTBs. If that is what you desire. If you desire something else, then buy what you want, not a boat anchor.
There are plenty of advantages of buying new. I curse every time I encounter bent axles, pitted cones, or perhaps mismatched parts that just don't work quite right together.