My opinion is that you would be better off buying the individual components. The misting system in the kit looks like overkill for a 24x24 enclosure, and the lighting(specifically the T5) might might be a bit undersized.
I agree with this. I'd build the kit myself. The FLChams extreme kit has an undersized linear UVB fixture and the ultimate mistking packaged with it has a lot of accessories you wont need. The starter kit mistking system is what I use for two enclosures. The ultimate kit is geared more toward multiple enclosures or many sprayer nozzles.
I personally for the enclosure I went with a DIYcages.com 48" tall cage, Dual 24" linear fixture with arcadia bulbs from lightyourreptiles.com, standard dome fixture for heat, starter mistking, and lots of live plants.
Supplements, I recently switched to Repashy Calcium Plus LoD for daily use to cover Calcium, multivitamins, and D3.
For drainage, I removed the DIYcages floor and use a washing machine drain pan from a local hardware store. Drilled a few holes near the center for water to drain into a Storage bin which I empty every few days. I have the enclosure sitting on 2 stainless steel bakers racks ziptied together to make a cage stand (since I couldn't find a rack with a 24" X 24" dimension...). Water collects in the drain pan and flows down to the collection bin through the wire rack.
I think between the cage, lighting, and mister I spent about $300. Personally, I think this sounds better than the $500 plus FLchams is charging. The majority of that cost is from the mistking system they put in that package.