H&S, Geo, or MTC?

[Volcano1]

Looking at calcium reactor for my system. 300 gallon display, 2 100 gallon sumps. Started on the sps bandwagon now, have about 25 medium colonies and 12 large clams, most of the rest Lps. Seeing my calcium demand go way up since adding sps. Looks like time for reactor.
Narrowed it down to H&S 200 cr. Geo 824, or MTC Procal.
I know the Geo and MTC will be enough, H&S may be slightly smaller.
Any real benefit with a dual stage over larger single stage unit?
Any comments on one vs the other?

 

[gasman059]

1-GEo
2-MTC PRO CAL
leaning towards GEO from personal experience plus superb customer service and built like a tank.

 

[Volcano1]

Yes , Geo does seem to be built well. Is the dual any better set up than a larger single chamber?