It's almost always money well spent. I too have heard nothing but good about Otterbar. You might also look at Ken Whiting's operation up on the Ottawa.
I personally love NOC. I went there growing up in the 80s and then in the 90s did a clinic there and then spend my grad school summers working in the outiftters store and chasing rain on my days off. The instructors, facility and gear are all top-notch. I know and have run many rivers with many of the intstructors and they are great people, very skilled at what they do. NOC is the mecca for whitewater instruction and retail on the east coast, and maybe in the whole country. They have everything from lake to V+ right in the backyard, so whatever your level is, they have rivers for it - and pretty much all but the Nanny have warm water, but even the Nanny is about 55 degrees (warm for a CO boater).
Bottom line, you probably can't go wrong with any of those three schools.
Join up, suckas.
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