Don't underestimate the "work" necessary for tube power amplifiers! Tube enthusiast will tell you it's no big deal, but it's similar to when motorheads tell you manual transmissions aren't any more demanding than auto trans. Aging tubes, heat from tubes, matching and biasing tubes, tube rolling, turn on/off procedures, warm up times for optimum listening, etc. Experienced audiophiles tend to downplay these issues. I am not trying to discourage you, but you need to proceed with your eyes open.
You've been offered some really good advice in this thread and I suspect that whatever way you'll go, you'll be very happy. Unfortunately, I think it will be the wrong decision. Rather than decide between tubes and solid state you could simply choose both. I've owned Rowland equipment for decades and think the company and products are first rate, but for the price of the Aeris and 625 you could buy a premium DAC, a solid state power amp and a tube power amp. Whenever the mood strikes you could switch from one power amp to the other and enjoy their respective benefits. To put some numbers to it, I'm talking about DACs in the $5k area and power amps in the $5-7k range.
You've been offered some really good advice in this thread and I suspect that whatever way you'll go, you'll be very happy. Unfortunately, I think it will be the wrong decision. Rather than decide between tubes and solid state you could simply choose both. I've owned Rowland equipment for decades and think the company and products are first rate, but for the price of the Aeris and 625 you could buy a premium DAC, a solid state power amp and a tube power amp. Whenever the mood strikes you could switch from one power amp to the other and enjoy their respective benefits. To put some numbers to it, I'm talking about DACs in the $5k area and power amps in the $5-7k range.