if you could give him a tank by himself, i say take it.
look at it this way. obviously you, nor almost anyone else can properly house that fish, however chances are your tank is larger than anyone elses that will buy it from the LFS.
it may end up cramped in your tank, but chances are high he will still get better care than from someone who dosent know jack about RTC, and may end up putting him in a 75g tank or something stupid.