When I was about 20, I bought a new GK 4x10 cab and a new 400RB.
Seemed like a perfect matchup to me. GK + GK =

, right? It was my first non-combo amp, so my knowledge of impedance was extremely limited. The (first set) of speakers blew within 33 days of purchase (was about my 8th time ever using the head/cab). Probably due to them selling me a head that was improperly matched for this cabinet, but was a "perfect" match according to the salesman.
I called them to see if it was covered under my warranty and they said no, because it was passed the 30 day return policy or something.
they would have to contact a GK distributer order the speakers and they would fix it for me - for a service charge. Or I could call GK and have the speakers shipped to my house and fix it myself/get it fixed at a no-name repair shop for a much larger charge. I had GC do the service, since I bought it there in the first place. They had it for 3 weeks.
What happened at a gig right away? Speakers blew during a set.
Next day, I called GK. They claimed it was a "bad batch" of speakers that they sent, and would send another set of 4 for free. Great, but I still don't know how to put them in...I contacted GC the next day to see if it was covered under their "service warranty" they said no, and had no record of me bringing it in and suggested I bring the cabinet in to get fixed - for another full service charge - and it took another 3 weeks to fix!!!
The best part!? They suggested I bring the GK 400 RB in as well because that "probably needs repair too". So I did, and they took my money, and 3 weeks of band rehearsals.
And my head clipped out during practice a month later and the speakers blew a third time. Ended up selling the cabinet back to them for $150 w/ blown speakers.
What I'm saying is, they took advantage of my lack of knowledge about something and used it to make more money. Maybe I'm the dumb one, but why would a "reputable" store have to make you feel like that in the first place???