Which would be preferable, an older Audio Research Corp. VT130 or a newer SS Rotel 1552?

Always remember in audio everything is a trade off.

Things to consider with the ARC VT130.

Made in 1995. Has it ever been recapped?

The amp requires tube biasing adjustments. (Power tubes as well as, I believe, the small signal tubes.) Do you have any experience biasing an early Audio Research VT series power Amp? I believe, the VT130 requires the small signal tubes must be biased. I have a pair of ARC VT50 amps. Biasing the signal tubes can be a real pain in the ***, is an under statement.

I would find out for sure if the signal tubes require biasing when installing new signal tubes. Especially the driver tubes.

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https://www.arcdb.ws/Database/VT130/ARC_VT130_manual.pdf  

https://www.arcdb.ws/Database/VT130/ARC_VT130_bias_adjustment.pdf

https://www.arcdb.ws/model/VT130

Edit: I could be wrong in saying the small signal tubes require biasing.

A quick look at the schematic I didn't see any adjustment pots.

https://www.arcdb.ws/model/VT130

Easily the ARC but with upgraded parts.

Happy Listening.

Listen to @ghdprentice. The man knows his Audio Research.

You're getting a lot of B&W hate in the replies. They aren't the speakers I would buy, but they aren't crap and they are perfectly capable of being engaging and musical.

I can't imagine upgrading beyond the 800 series B&W speakers and expecting to get high-end performance from your Rotel amp. With the VT130, you will find that the 6550s, if sources from ARC, last a long time. I drove the crap out of my Classic 60 for three years (also 8 output tubes), and when I tested the tubes, the drivers needed to be replaced but the output tubes still measured at or above 100% of new specs. All 8 of them 

The VT130 uses 6922s for input tubes, which is not a great tube design and they do not last long, but they are small, inexpensive, and readily available. Keep extras on hand, and when your amp starts sounding more like the Rotel, put new 6922s in there, and you will be happy. Send the 6550s and driver tubes to Western Glow every two years for testing. You'll never look back.

I have a VT130. In fact it's on my old virtual system page here. I re-tubed it using ARC tubes which was expensive. However my dealer let me have them at his cost so not that painful. 

I acquired the amp "by accident". It was thrown in an a SP15 purchase. It didn't work right- it was red plating and blew a screening resistor. A $10 resistor from ARC and a new v13 tube and a pair of 6550s came next.  I got a local guitar amp repair shop to bias it for me and hooked it up and viola! It was alive!

Back when all this happened I had never owned an ARC amp. Was I ever in for a surprise. Take all the audiophile superlatives and double them. I literally had tears in my eyes hearing things in my favorite music that I hadn't heard before and didn't- couldn't know were there. It was like a blind man could see for the first time. Well, not that dramatic but you get the point- it was the joy of rediscovering music that made me love that old amp.

William Zane "Bill" Johnson founder of ARC was the designer. It was the first of the new "large format" amps by ARC. Bill was proud of that amp and is quoted as saying "It's 2 amps on the same chassis. Inputs in the front, outputs in the back- like it should me".  The VT130SE is the nearly same amp with a big faceplate and meters. It sells for a lot more and IMO not worth it. 

There are 2 for sale out there now- TMR has one and AGon has one. Both asking $2,000 which is about right. 

If the amp you buy has low hours on the tubes you will have a costs next-to-nothing transformative tube amp experience.  If you don't love it you can get most all your money back out if it in the resale market.

Your speakers could use a little taming. I know them well. A SS amp with your speakers will make the highs harsh. Just my opinion. 

Therefore; skip the Rotel and buy the VT130.