I was planing on buying online a B-51 AT-112 but there are a lot of reviews saying that they don't function well...A LOT!!

I don't know if I should buy it anymore...any owners out there, or people who just know, please help my cause!!
I have the At-100 which i think is just the head and not a combo and I love it.
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I owned one. I bought it the first time about 3 years ago I think? Well 6 months into me owning it, it started producing this awful THUD at loud volumes, almost like the bass was way past 10 when it wasnt. It was horrible. It couldnt be played at loud volumes. Anyway, I took it back and got it replaced for free. I had the second one about 2 years. I never had a problem with it until the end. One day, I flipped my amp on, and it immediately shut off. I had no clue what was wrong with it. I replaced the fuse, check the connections. Nothing. I took it to my shop, and got it *fixed* (I use that term loosely). I got it home, played it for 20 minutes and it stopped working again. This is probably partially the shops fault, but they did get it to turn on again.

Anywho here's where my nightmare began. I sent the amp back to them. They found a faulty transformer I believe. Its been a while ago, so I dont remember exactly. Something about the thermostat on the transformer if I remember correctly. So they contacted b-52 about it. B-52 wouldnt send out just the thermostat. They wanted to send the whole transformer, which wasnt needed evidently. Finally, one day the said they would ship it - 2 day air. I live in ohio and their factory is located in california - perfectly reasonable. Well A MONTH went by and I still didnt have it. Finally, the amp tech called b-52 and they told the tech they werent going to ship the part without some sort of proof of purchase. At this time mind you, it hadnt been under warranty for 2 years. All I wanted was the part for the amp, and I was going to pay for the part. Its not like I was going to get it for free. Anyway, I had to track down the guy i bought it from at guitar center, and fax them the receipt. It was a horrible nightmare. In the end, the tech didnt charge me for the repair because of the huge hassle, and since then, I know the shop has stopped accepting b-52 products in light of my situation.

As far as the amp goes - its a beast. I loved it. But unfortunately, you better hope you get a good unit, because if not, its going to be expensive and a long wait if you have to go through b-52 to get the part. I read a lot of the reviews too. Bad reverb, overheating.. etc. I never had any of those issues. Mine just completely went to crap.
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