Personally, I'd prefer to buy locally simply for the fact that in case something breaks (like my Pod XT did twice in the first year), I can take it right in & get it serviced for free (with the warranty of course). Whereas when buying online, especially used stuff, you're taking the seller's (assuming it's not an online store) word that it's in the shape that actually is, let alone the fact that either a) they may or may not actually ship it or b) it won't get damaged or lost.
Like others have said though, most local shops just don't have the kind of selection online stores have access to. I mean out of the 2 or 3 shops here in town, the only non-tube head for sale is an Ibanez Tone-Blaster, even though there are dozens more available. Their sales are targeted to bedroom / basement band players who are mostly looking for cheap Epiphones or Fenders and combo amps. Mind you, one store just recently started stocking a few Mesa heads, so at least it's a start. Now if only they'd handle a little used gear, it'd be soooo much better.
