ARC Select Worth Price?

I am not a tube roller in general, at least not for Audio Research equipment. I know Audio Research has put tremendous design effort into achieving the exact sound you get with the stock tubes and changing tubes changes the sound. I bought Audio Research for the exact sound I get.

 For more generic sounding equipment or less expensive I would consider tube rolling. And have in my PrimaLuna for example and my Woo Head amps. 

Having said all of that. One of my audiogon friends tried and liked a NOS General Electric 6550... which goes in the power supply circuit on the ARC Ref preamp, phono stages and DAC. So, just for fun I tried one. There was not a huge difference... but it was just a tad warmer more tubey. Not a lot... subtle. So I kept it and put one in my DAC. But as I said, not a huge change. If I had really trebly / hot speakers it would probably make a bigger difference. 

I did get a response from Upscale. He said to buy ARC select only if you have Audio Research Equipment and that these tubes are selected to pass higher standards so to hold up better in ARC equipment. To that effect. 

I recently retubed my ARC Ref 6SE with my backup set and ordered a new backup set from Upscale. My preference is to order from ARC as they do a lot of testing. But I was trying to save a few dollars. I felt obligated to buy the ARC select from Upscale... assuming they were testing more like ARC would do. I asked if they were matched, the answer is yes. If you order more than one... I ordered seven, they are all matched if on the same order. I just sent a follow up message asking the differences between regular and ARC Select. 

Although I listen two to three hours a day... that still means it is years between retubing... so, hard to get much experience on different tubes.