After sharpening both sides of the blade place it on the kits cone-shaped balancer. If one side dips below the other continue sharpening it until the blade rests level. Return the sharpened blades to the mower and reattach. If you have a torque wrench its a good idea to use it here. Often you need to tighten the blade mounting bolt/bolts to a specific tightness level. Typically measured in pound-feet your instruction manual should list these specs. For example my personal machine the Honda HRR216VKA between 36 to 43 lb-ft of torque is required.
More than 2100 buyers on Home Depots site recommend the Toro Recycler 20333. The most helpful reviewer found the powerful engine did an excellent job of chopping through foot-high grass and the rear wheel drive gave him power while turning. He also mentioned that he could almost jog with it. Another buyer notes that his Toro still runs well after three years of questionable maintenance. He does note a couple negatives: It is a bit louder than the Honda and if you go to fast the mulch is not fine enough.
Your Best Digs also recommends the Sun Joe mower but the reviewer also added a number of caveats. He found it will get the job done if you prefer to only bag and just have $100 to spend. However the clippings compartment filled up quickly for him. And the height adjuster felt flimsy and required adjustments on each wheel.